Name

outlook.pst — format of MS Outlook .pst file

Synopsis

outlook.pst

Overview

Low level or primitive items in a .pst file are identified by an I_ID value. Higher level or composite items in a .pst file are identified by a D_ID value. There are two separate b-trees indexed by these I_ID and D_ID values. Starting with Outlook 2003, the file format changed from one with 32 bit pointers, to one with 64 bit pointers. We describe both formats here.

32 bit File Header

The 32 bit file header is located at offset 0 in the .pst file.

0000  21 42 44 4e 49 f8 64 d9  53 4d 0e 00 13 00 01 01
0010  00 00 00 00 00 00 00 00  50 d6 03 00 bd 1e 02 00
0020  08 4c 00 00 00 04 00 00  00 04 00 00 0f 04 00 00
0030  0d 40 00 00 99 0a 01 00  18 04 00 00 0d 40 00 00
0040  0d 40 00 00 11 80 00 00  02 04 00 00 0a 04 00 00
0050  00 04 00 00 00 04 00 00  0f 04 00 00 0f 04 00 00
0060  0f 04 00 00 0d 40 00 00  00 04 00 00 00 04 00 00
0070  04 40 00 00 00 04 00 00  00 04 00 00 00 04 00 00
0080  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
0090  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
00a0  0c 09 00 00 00 00 00 00  00 04 27 00 00 24 23 00
00b0  c0 09 0a 00 00 c8 00 00  bc 1e 02 00 00 7e 0c 00
00c0  b4 1e 02 00 00 54 00 00  01 00 00 00 23 55 44 d1
00d0  5a 4f ce 6b 80 ff ff ff  00 00 00 00 00 00 00 00
00e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
00f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0100  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0110  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0120  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0130  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0140  00 00 00 00 00 00 00 00  00 00 00 00 3f ff ff ff
0150  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0160  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0170  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0180  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0190  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01a0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01b0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01c0  ff ff ff ff ff ff ff ff  ff ff ff ff 80 01 00 00
01d0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
01e0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
01f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00

0000  signature       [4 bytes] 0x4e444221 constant
000a  indexType       [1 byte]  0x0e       constant
01cd  encryptionType  [1 byte]  0x01       in this case
00a8  total file size [4 bytes] 0x270400   in this case
00c0  backPointer1    [4 bytes] 0x021eb4   in this case
00c4  offsetIndex1    [4 bytes] 0x005400   in this case
00b8  backPointer2    [4 bytes] 0x021ebc   in this case
00bc  offsetIndex2    [4 bytes] 0x0c7e00   in this case

We only support index types 0x0e, 0x0f, 0x15, and 0x17, and encryption types 0x00, 0x01 and 0x02. Index type 0x0e is the older 32 bit Outlook format. Index type 0x0f seems to be rare, and so far the data seems to be identical to that in type 0x0e files. Index type 0x17 is the newer 64 bit Outlook format. Index type 0x15 seems to be rare, and according to the libpff project should have the same format as type 0x17 files. It was found in a 64-bit pst file created by Visual Recovery. It may be that index types less than 0x10 are 32 bit, and index types greater than or equal to 0x10 are 64 bit, and the low order four bits of the index type is some subtype or minor version number.

Encryption type 0x00 is no encryption, type 0x01 is "compressible" encryption which is a simple substitution cipher, and type 0x02 is "strong" encryption, which is a simple three rotor Enigma cipher from WWII.

offsetIndex1 is the file offset of the root of the index1 b-tree, which contains (I_ID, offset, size, unknown) tuples for each item in the file. backPointer1 is the value that should appear in the parent pointer of that root node.

offsetIndex2 is the file offset of the root of the index2 b-tree, which contains (D_ID, DESC-I_ID, TREE-I_ID, PARENT-D_ID) tuples for each item in the file. backPointer2 is the value that should appear in the parent pointer of that root node.

64 bit File Header

The 64 bit file header is located at offset 0 in the .pst file.

0000  21 42 44 4e 03 02 23 b2  53 4d 17 00 13 00 01 01
0010  00 00 00 00 00 00 00 00  04 00 00 00 01 00 00 00
0020  8b 00 00 00 00 00 00 00  1d 00 00 00 00 04 00 00
0030  00 04 00 00 04 04 00 00  00 40 00 00 02 00 01 00
0040  00 04 00 00 00 04 00 00  00 04 00 00 00 80 00 00
0050  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
0060  04 04 00 00 04 04 00 00  04 04 00 00 00 04 00 00
0070  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
0080  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
0090  00 04 00 00 00 04 00 00  00 04 00 00 00 04 00 00
00a0  00 04 00 00 00 04 00 00  02 04 00 00 00 00 00 00
00b0  00 00 00 00 00 00 00 00  00 24 04 00 00 00 00 00
00c0  00 44 00 00 00 00 00 00  00 71 03 00 00 00 00 00
00d0  00 22 00 00 00 00 00 00  83 00 00 00 00 00 00 00
00e0  00 6a 00 00 00 00 00 00  8a 00 00 00 00 00 00 00
00f0  00 60 00 00 00 00 00 00  01 00 00 00 00 00 00 00
0100  ff 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0110  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0120  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0130  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0140  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0150  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0160  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0170  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0180  7f ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0190  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01a0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01b0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01c0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01d0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01e0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
01f0  ff ff ff ff ff ff ff ff  ff ff ff ff ff ff ff ff
0200  80 00 00 00 e8 00 00 00  00 00 00 00 c4 68 cb 89

0000  signature       [4 bytes] 0x4e444221 constant
000a  indexType       [1 byte]  0x17       constant
0201  encryptionType  [1 byte]  0x00       in this case
00b8  total file size [8 bytes] 0x042400   in this case
00e8  backPointer1    [8 bytes] 0x00008a   in this case
00f0  offsetIndex1    [8 bytes] 0x006000   in this case
00d8  backPointer2    [8 bytes] 0x000083   in this case
00e0  offsetIndex2    [8 bytes] 0x006a00   in this case

32 bit Index 1 Node

The 32 bit index1 b-tree nodes are 512 byte blocks with the following format.

0000  04 00 00 00  8a 1e 02 00  00 1c 0b 00
000c  58 27 03 00  b3 1e 02 00  00 52 00 00
0018  00 00 00 00  00 00 00 00  00 00 00 00
0024  00 00 00 00  00 00 00 00  00 00 00 00
0030  00 00 00 00  00 00 00 00  00 00 00 00
003c  00 00 00 00  00 00 00 00  00 00 00 00
0048  00 00 00 00  00 00 00 00  00 00 00 00
0054  00 00 00 00  00 00 00 00  00 00 00 00
0060  00 00 00 00  00 00 00 00  00 00 00 00
006c  00 00 00 00  00 00 00 00  00 00 00 00
0078  00 00 00 00  00 00 00 00  00 00 00 00
0084  00 00 00 00  00 00 00 00  00 00 00 00
0090  00 00 00 00  00 00 00 00  00 00 00 00
009c  00 00 00 00  00 00 00 00  00 00 00 00
00a8  00 00 00 00  00 00 00 00  00 00 00 00
00b4  00 00 00 00  00 00 00 00  00 00 00 00
00c0  00 00 00 00  00 00 00 00  00 00 00 00
00cc  00 00 00 00  00 00 00 00  00 00 00 00
00d8  00 00 00 00  00 00 00 00  00 00 00 00
00e4  00 00 00 00  00 00 00 00  00 00 00 00
00f0  00 00 00 00  00 00 00 00  00 00 00 00
00fc  00 00 00 00  00 00 00 00  00 00 00 00
0108  00 00 00 00  00 00 00 00  00 00 00 00
0114  00 00 00 00  00 00 00 00  00 00 00 00
0120  00 00 00 00  00 00 00 00  00 00 00 00
012c  00 00 00 00  00 00 00 00  00 00 00 00
0138  00 00 00 00  00 00 00 00  00 00 00 00
0144  00 00 00 00  00 00 00 00  00 00 00 00
0150  00 00 00 00  00 00 00 00  00 00 00 00
015c  00 00 00 00  00 00 00 00  00 00 00 00
0168  00 00 00 00  00 00 00 00  00 00 00 00
0174  00 00 00 00  00 00 00 00  00 00 00 00
0180  00 00 00 00  00 00 00 00  00 00 00 00
018c  00 00 00 00  00 00 00 00  00 00 00 00
0198  00 00 00 00  00 00 00 00  00 00 00 00
01a4  00 00 00 00  00 00 00 00  00 00 00 00
01b0  00 00 00 00  00 00 00 00  00 00 00 00
01bc  00 00 00 00  00 00 00 00  00 00 00 00
01c8  00 00 00 00  00 00 00 00  00 00 00 00
01d4  00 00 00 00  00 00 00 00  00 00 00 00
01e0  00 00 00 00  00 00 00 00  00 00 00 00
01ec  00 00 00 00  02 29 0c 02  80 80 b6 4a
01f8  b4 1e 02 00  27 9c cc 56

01f0  itemCount       [1 byte]  0x02       in this case
01f1  maxItemCount    [1 byte]  0x29       constant
01f2  itemSize        [1 byte]  0x0c       constant
01f3  nodeLevel       [1 byte]  0x02       in this case
01f8  backPointer     [4 bytes] 0x021eb4   in this case

The itemCount specifies the number of 12 byte records that are active. The nodeLevel is non-zero for this style of nodes. The leaf nodes have a different format. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a triple of (I_ID, backPointer, offset) where the offset points to the next deeper node in the tree, the backPointer value must match the backPointer in that deeper node, and I_ID is the lowest I_ID value in the subtree.

64 bit Index 1 Node

The 64 bit index1 b-tree nodes are 512 byte blocks with the following format.

0000  04 00 00 00  00 00 00 00  88 00 00 00
000C  00 00 00 00  00 48 00 00  00 00 00 00
0018  74 00 00 00  00 00 00 00  86 00 00 00
0024  00 00 00 00  00 54 00 00  00 00 00 00
0030  00 00 00 00  00 00 00 00  00 00 00 00
003C  00 00 00 00  00 00 00 00  00 00 00 00
0048  00 00 00 00  00 00 00 00  00 00 00 00
0054  00 00 00 00  00 00 00 00  00 00 00 00
0060  00 00 00 00  00 00 00 00  00 00 00 00
006C  00 00 00 00  00 00 00 00  00 00 00 00
0078  00 00 00 00  00 00 00 00  00 00 00 00
0084  00 00 00 00  00 00 00 00  00 00 00 00
0090  00 00 00 00  00 00 00 00  00 00 00 00
009C  00 00 00 00  00 00 00 00  00 00 00 00
00A8  00 00 00 00  00 00 00 00  00 00 00 00
00B4  00 00 00 00  00 00 00 00  00 00 00 00
00C0  00 00 00 00  00 00 00 00  00 00 00 00
00CC  00 00 00 00  00 00 00 00  00 00 00 00
00D8  00 00 00 00  00 00 00 00  00 00 00 00
00E4  00 00 00 00  00 00 00 00  00 00 00 00
00F0  00 00 00 00  00 00 00 00  00 00 00 00
00FC  00 00 00 00  00 00 00 00  00 00 00 00
0108  00 00 00 00  00 00 00 00  00 00 00 00
0114  00 00 00 00  00 00 00 00  00 00 00 00
0120  00 00 00 00  00 00 00 00  00 00 00 00
012C  00 00 00 00  00 00 00 00  00 00 00 00
0138  00 00 00 00  00 00 00 00  00 00 00 00
0144  00 00 00 00  00 00 00 00  00 00 00 00
0150  00 00 00 00  00 00 00 00  00 00 00 00
015C  00 00 00 00  00 00 00 00  00 00 00 00
0168  00 00 00 00  00 00 00 00  00 00 00 00
0174  00 00 00 00  00 00 00 00  00 00 00 00
0180  00 00 00 00  00 00 00 00  00 00 00 00
018C  00 00 00 00  00 00 00 00  00 00 00 00
0198  00 00 00 00  00 00 00 00  00 00 00 00
01A4  00 00 00 00  00 00 00 00  00 00 00 00
01B0  00 00 00 00  00 00 00 00  00 00 00 00
01BC  00 00 00 00  00 00 00 00  00 00 00 00
01C8  00 00 00 00  00 00 00 00  00 00 00 00
01D4  00 00 00 00  00 00 00 00  00 00 00 00
01E0  00 00 00 00  00 00 00 00  02 14 18 01
01EC  00 00 00 00  80 80 8a 60  68 e5 b5 19
01F8  8a 00 00 00  00 00 00 00

01e8  itemCount       [1 byte]  0x02       in this case
01e9  maxItemCount    [1 byte]  0x14       constant
01ea  itemSize        [1 byte]  0x18       constant
01eb  nodeLevel       [1 byte]  0x01       in this case
01f8  backPointer     [8 bytes] 0x00008a   in this case

The itemCount specifies the number of 24 byte records that are active. The nodeLevel is non-zero for this style of nodes. The leaf nodes have a different format. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a triple of (I_ID, backPointer, offset) where the offset points to the next deeper node in the tree, the backPointer value must match the backPointer in that deeper node, and I_ID is the lowest I_ID value in the subtree.

32 bit Index 1 Leaf Node

The 32 bit index1 b-tree leaf nodes are 512 byte blocks with the following format.

0000  04 00 00 00  00 58 00 00  64 00  0f 00
000c  08 00 00 00  80 58 00 00  ac 00  06 00
0018  0c 00 00 00  40 59 00 00  ac 00  06 00
0024  10 00 00 00  00 5a 00 00  bc 00  03 00
0030  14 00 00 00  00 5b 00 00  a4 00  02 00
003c  18 00 00 00  c0 5b 00 00  64 00  02 00
0048  1c 00 00 00  40 5c 00 00  5c 00  02 00
0054  50 00 00 00  80 62 00 00  60 00  02 00
0060  74 00 00 00  00 77 00 00  5e 00  02 00
006c  7c 00 00 00  80 77 00 00  66 00  02 00
0078  84 00 00 00  00 76 00 00  ca 00  02 00
0084  88 00 00 00  00 63 00 00  52 00  02 00
0090  90 00 00 00  00 79 00 00  58 00  02 00
009c  cc 00 00 00  c0 61 00 00  76 00  02 00
00a8  e0 00 00 00  00 61 00 00  74 00  02 00
00b4  f4 00 00 00  80 65 00 00  6e 00  02 00
00c0  8c 01 00 00  40 60 00 00  70 00  02 00
00cc  ea 01 00 00  80 61 00 00  10 00  02 00
00d8  ec 01 00 00  40 8a 00 00  f3 01  02 00
00e4  f0 01 00 00  80 93 00 00  f4 1f  02 00
00f0  fa 01 00 00  c0 7f 00 00  10 00  02 00
00fc  00 02 00 00  00 89 00 00  34 01  02 00
0108  1c 02 00 00  40 ec 00 00  12 06  02 00
0114  22 02 00 00  00 84 00 00  10 00  02 00
0120  24 02 00 00  c0 ea 00 00  3c 01  02 00
012c  40 02 00 00  00 f4 00 00  0a 06  02 00
0138  46 02 00 00  40 8c 00 00  10 00  02 00
0144  48 02 00 00  80 f2 00 00  36 01  02 00
0150  64 02 00 00  80 fb 00 00  bf 07  02 00
015c  6a 02 00 00  80 63 00 00  10 00  02 00
0168  6c 02 00 00  40 fa 00 00  2a 01  02 00
0174  6c 02 00 00  40 fa 00 00  2a 01  02 00
0180  6c 02 00 00  40 fa 00 00  2a 01  02 00
018c  6c 02 00 00  40 fa 00 00  2a 01  02 00
0198  6c 02 00 00  40 fa 00 00  2a 01  02 00
01a4  6c 02 00 00  40 fa 00 00  2a 01  02 00
01b0  64 02 00 00  80 fb 00 00  bf 07  02 00
01bc  64 02 00 00  80 fb 00 00  bf 07  02 00
01c8  64 02 00 00  80 fb 00 00  bf 07  02 00
01d4  64 02 00 00  80 fb 00 00  bf 07  02 00
01e0  64 02 00 00  80 fb 00 00  bf 07  02 00
01ec  00 00 00 00  1f 29 0c 00  80 80  5b b3
01f8  5a 67 01 00  4f ae 70 a7

01f0  itemCount       [1 byte]  0x1f       in this case
01f1  maxItemCount    [1 byte]  0x29       constant
01f2  itemSize        [1 byte]  0x0c       constant
01f3  nodeLevel       [1 byte]  0x00       defines a leaf node
01f8  backPointer     [4 bytes] 0x01675a   in this case

The itemCount specifies the number of 12 byte records that are active. The nodeLevel is zero for these leaf nodes. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a tuple of (I_ID, offset, size, unknown) The two low order bits of the I_ID value seem to be flags. I have never seen a case with bit zero set. Bit one indicates that the item is not encrypted. Note that references to these I_ID values elsewhere may have the low order bit set (and I don't know what that means), but when we do the search in this tree we need to clear that bit so that we can find the correct item.

64 bit Index 1 Leaf Node

The 64 bit index1 b-tree leaf nodes are 512 byte blocks with the following format.

0000  04 00 00 00  00 00 00 00  00 58 00 00
000C  00 00 00 00  6c 00 05 00  00 00 00 00
0018  08 00 00 00  00 00 00 00  80 58 00 00
0024  00 00 00 00  b4 00 06 00  d8 22 37 08
0030  0c 00 00 00  00 00 00 00  80 59 00 00
003C  00 00 00 00  ac 00 07 00  d8 22 37 08
0048  10 00 00 00  00 00 00 00  40 5a 00 00
0054  00 00 00 00  bc 00 03 00  d8 22 37 08
0060  14 00 00 00  00 00 00 00  40 5b 00 00
006C  00 00 00 00  a4 00 02 00  d8 22 37 08
0078  18 00 00 00  00 00 00 00  00 5c 00 00
0084  00 00 00 00  64 00 02 00  d8 22 37 08
0090  1c 00 00 00  00 00 00 00  80 5c 00 00
009C  00 00 00 00  5c 00 02 00  d8 22 37 08
00A8  24 00 00 00  00 00 00 00  80 5d 00 00
00B4  00 00 00 00  72 00 02 00  d8 22 37 08
00C0  34 00 00 00  00 00 00 00  00 70 00 00
00CC  00 00 00 00  8c 00 02 00  00 0d 00 00
00D8  38 00 00 00  00 00 00 00  c0 71 00 00
00E4  00 00 00 00  5c 00 02 00  d8 22 9c 00
00F0  40 00 00 00  00 00 00 00  40 72 00 00
00FC  00 00 00 00  26 00 02 00  d8 22 9c 00
0108  4c 00 00 00  00 00 00 00  80 5f 00 00
0114  00 00 00 00  3e 00 02 00  d8 22 9c 00
0120  5c 00 00 00  00 00 00 00  c0 76 00 00
012C  00 00 00 00  8c 00 02 00  d8 22 9c 00
0138  64 00 00 00  00 00 00 00  40 75 00 00
0144  00 00 00 00  76 00 02 00  d8 22 9c 00
0150  6c 00 00 00  00 00 00 00  c0 73 00 00
015C  00 00 00 00  5e 00 02 00  d8 22 9c 00
0168  70 00 00 00  00 00 00 00  80 72 00 00
0174  00 00 00 00  1e 01 02 00  d8 22 9c 00
0180  70 00 00 00  00 00 00 00  80 72 00 00
018C  00 00 00 00  1e 01 02 00  d8 22 9c 00
0198  70 00 00 00  00 00 00 00  80 72 00 00
01A4  00 00 00 00  1e 01 02 00  d8 22 9c 00
01B0  74 00 00 00  00 00 00 00  40 74 00 00
01BC  00 00 00 00  e0 00 02 00  d8 22 9c 00
01C8  7c 00 00 00  00 00 00 00  80 77 00 00
01D4  00 00 00 00  dc 00 02 00  d8 22 9c 00
01E0  00 00 00 00  00 00 00 00  10 14 18 00
01EC  00 00 00 00  80 80 88 48  3f 50 0b 04
01F8  88 00 00 00  00 00 00 00

01e8  itemCount       [1 byte]  0x10       in this case
01e9  maxItemCount    [1 byte]  0x14       constant
01ea  itemSize        [1 byte]  0x18       constant
01eb  nodeLevel       [1 byte]  0x00       defines a leaf node
01f8  backPointer     [8 bytes] 0x000088   in this case

The itemCount specifies the number of 24 byte records that are active. The nodeLevel is zero for these leaf nodes. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a tuple of (I_ID, offset, size, unknown) The two low order bits of the I_ID value seem to be flags. I have never seen a case with bit zero set. Bit one indicates that the item is not encrypted. Note that references to these I_ID values elsewhere may have the low order bit set (and I don't know what that means), but when we do the search in this tree we need to clear that bit so that we can find the correct item.

32 bit Index 2 Node

The 32 bit index2 b-tree nodes are 512 byte blocks with the following format.

0000  21 00 00 00  bb 1e 02 00  00 e2 0b 00
000c  64 78 20 00  8c 1e 02 00  00 dc 0b 00
0018  00 00 00 00  00 00 00 00  00 00 00 00
0024  00 00 00 00  00 00 00 00  00 00 00 00
0030  00 00 00 00  00 00 00 00  00 00 00 00
003c  00 00 00 00  00 00 00 00  00 00 00 00
0048  00 00 00 00  00 00 00 00  00 00 00 00
0054  00 00 00 00  00 00 00 00  00 00 00 00
0060  00 00 00 00  00 00 00 00  00 00 00 00
006c  00 00 00 00  00 00 00 00  00 00 00 00
0078  00 00 00 00  00 00 00 00  00 00 00 00
0084  00 00 00 00  00 00 00 00  00 00 00 00
0090  00 00 00 00  00 00 00 00  00 00 00 00
009c  00 00 00 00  00 00 00 00  00 00 00 00
00a8  00 00 00 00  00 00 00 00  00 00 00 00
00b4  00 00 00 00  00 00 00 00  00 00 00 00
00c0  00 00 00 00  00 00 00 00  00 00 00 00
00cc  00 00 00 00  00 00 00 00  00 00 00 00
00d8  00 00 00 00  00 00 00 00  00 00 00 00
00e4  00 00 00 00  00 00 00 00  00 00 00 00
00f0  00 00 00 00  00 00 00 00  00 00 00 00
00fc  00 00 00 00  00 00 00 00  00 00 00 00
0108  00 00 00 00  00 00 00 00  00 00 00 00
0114  00 00 00 00  00 00 00 00  00 00 00 00
0120  00 00 00 00  00 00 00 00  00 00 00 00
012c  00 00 00 00  00 00 00 00  00 00 00 00
0138  00 00 00 00  00 00 00 00  00 00 00 00
0144  00 00 00 00  00 00 00 00  00 00 00 00
0150  00 00 00 00  00 00 00 00  00 00 00 00
015c  00 00 00 00  00 00 00 00  00 00 00 00
0168  00 00 00 00  00 00 00 00  00 00 00 00
0174  00 00 00 00  00 00 00 00  00 00 00 00
0180  00 00 00 00  00 00 00 00  00 00 00 00
018c  00 00 00 00  00 00 00 00  00 00 00 00
0198  00 00 00 00  00 00 00 00  00 00 00 00
01a4  00 00 00 00  00 00 00 00  00 00 00 00
01b0  00 00 00 00  00 00 00 00  00 00 00 00
01bc  00 00 00 00  00 00 00 00  00 00 00 00
01c8  00 00 00 00  00 00 00 00  00 00 00 00
01d4  00 00 00 00  00 00 00 00  00 00 00 00
01e0  00 00 00 00  00 00 00 00  00 00 00 00
01ec  00 00 00 00  02 29 0c 02  81 81 b2 60
01f8  bc 1e 02 00  7e 70 dc e3

01f0  itemCount       [1 byte]  0x02       in this case
01f1  maxItemCount    [1 byte]  0x29       constant
01f2  itemSize        [1 byte]  0x0c       constant
01f3  nodeLevel       [1 byte]  0x02       in this case
01f8  backPointer     [4 bytes] 0x021ebc   in this case

The itemCount specifies the number of 12 byte records that are active. The nodeLevel is non-zero for this style of nodes. The leaf nodes have a different format. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a triple of (D_ID, backPointer, offset) where the offset points to the next deeper node in the tree, the backPointer value must match the backPointer in that deeper node, and D_ID is the lowest D_ID value in the subtree.

64 bit Index 2 Node

The 64 bit index2 b-tree nodes are 512 byte blocks with the following format.

0000  21 00 00 00  00 00 00 00  77 00 00 00
000C  00 00 00 00  00 56 00 00  00 00 00 00
0018  4c 06 00 00  00 00 00 00  82 00 00 00
0024  00 00 00 00  00 68 00 00  00 00 00 00
0030  4f 80 00 00  00 00 00 00  84 00 00 00
003C  00 00 00 00  00 6e 00 00  00 00 00 00
0048  00 00 00 00  00 00 00 00  00 00 00 00
0054  00 00 00 00  00 00 00 00  00 00 00 00
0060  00 00 00 00  00 00 00 00  00 00 00 00
006C  00 00 00 00  00 00 00 00  00 00 00 00
0078  00 00 00 00  00 00 00 00  00 00 00 00
0084  00 00 00 00  00 00 00 00  00 00 00 00
0090  00 00 00 00  00 00 00 00  00 00 00 00
009C  00 00 00 00  00 00 00 00  00 00 00 00
00A8  00 00 00 00  00 00 00 00  00 00 00 00
00B4  00 00 00 00  00 00 00 00  00 00 00 00
00C0  00 00 00 00  00 00 00 00  00 00 00 00
00CC  00 00 00 00  00 00 00 00  00 00 00 00
00D8  00 00 00 00  00 00 00 00  00 00 00 00
00E4  00 00 00 00  00 00 00 00  00 00 00 00
00F0  00 00 00 00  00 00 00 00  00 00 00 00
00FC  00 00 00 00  00 00 00 00  00 00 00 00
0108  00 00 00 00  00 00 00 00  00 00 00 00
0114  00 00 00 00  00 00 00 00  00 00 00 00
0120  00 00 00 00  00 00 00 00  00 00 00 00
012C  00 00 00 00  00 00 00 00  00 00 00 00
0138  00 00 00 00  00 00 00 00  00 00 00 00
0144  00 00 00 00  00 00 00 00  00 00 00 00
0150  00 00 00 00  00 00 00 00  00 00 00 00
015C  00 00 00 00  00 00 00 00  00 00 00 00
0168  00 00 00 00  00 00 00 00  00 00 00 00
0174  00 00 00 00  00 00 00 00  00 00 00 00
0180  00 00 00 00  00 00 00 00  00 00 00 00
018C  00 00 00 00  00 00 00 00  00 00 00 00
0198  00 00 00 00  00 00 00 00  00 00 00 00
01A4  00 00 00 00  00 00 00 00  00 00 00 00
01B0  00 00 00 00  00 00 00 00  00 00 00 00
01BC  00 00 00 00  00 00 00 00  00 00 00 00
01C8  00 00 00 00  00 00 00 00  00 00 00 00
01D4  00 00 00 00  00 00 00 00  00 00 00 00
01E0  00 00 00 00  00 00 00 00  03 14 18 01
01EC  00 00 00 00  81 81 83 6a  49 da f3 d3
01F8  83 00 00 00  00 00 00 00

01e8  itemCount       [1 byte]  0x03       in this case
01e9  maxItemCount    [1 byte]  0x14       constant
01ea  itemSize        [1 byte]  0x18       constant
01eb  nodeLevel       [1 byte]  0x01       in this case
01f8  backPointer     [8 bytes] 0x000083   in this case

The itemCount specifies the number of 24 byte records that are active. The nodeLevel is non-zero for this style of nodes. The leaf nodes have a different format. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a triple of (D_ID, backPointer, offset) where the offset points to the next deeper node in the tree, the backPointer value must match the backPointer in that deeper node, and D_ID is the lowest D_ID value in the subtree.

32 bit Index 2 Leaf Node

The 32 bit index2 b-tree leaf nodes are 512 byte blocks with the following format.

0000  21 00 00 00  38 e6 00 00  00 00 00 00  00 00 00 00
0010  61 00 00 00  2c a8 02 00  36 a8 02 00  00 00 00 00
0020  22 01 00 00  20 a2 02 00  00 00 00 00  22 01 00 00
0030  2d 01 00 00  88 7b 03 00  00 00 00 00  00 00 00 00
0040  2e 01 00 00  08 00 00 00  00 00 00 00  00 00 00 00
0050  2f 01 00 00  0c 00 00 00  00 00 00 00  00 00 00 00
0060  e1 01 00 00  00 00 00 00  00 00 00 00  00 00 00 00
0070  01 02 00 00  b4 e4 02 00  00 00 00 00  00 00 00 00
0080  61 02 00 00  a0 e4 02 00  00 00 00 00  00 00 00 00
0090  0d 06 00 00  04 00 00 00  00 00 00 00  00 00 00 00
00A0  0e 06 00 00  08 00 00 00  00 00 00 00  00 00 00 00
00B0  0f 06 00 00  0c 00 00 00  00 00 00 00  00 00 00 00
00C0  10 06 00 00  10 00 00 00  00 00 00 00  00 00 00 00
00D0  2b 06 00 00  84 00 00 00  00 00 00 00  00 00 00 00
00E0  4c 06 00 00  1c 00 00 00  00 00 00 00  00 00 00 00
00F0  71 06 00 00  18 00 00 00  00 00 00 00  00 00 00 00
0100  92 06 00 00  14 00 00 00  00 00 00 00  00 00 00 00
0110  23 22 00 00  14 a0 02 00  00 00 00 00  22 01 00 00
0120  26 22 00 00  00 00 00 00  00 00 00 00  00 00 00 00
0130  27 22 00 00  1c a0 02 00  00 00 00 00  00 00 00 00
0140  22 80 00 00  50 00 00 00  00 00 00 00  22 01 00 00
0150  2d 80 00 00  f8 9f 02 00  00 00 00 00  00 00 00 00
0160  2e 80 00 00  08 00 00 00  00 00 00 00  00 00 00 00
0170  2f 80 00 00  34 e6 00 00  00 00 00 00  00 00 00 00
0180  42 80 00 00  3c 6d 02 00  00 00 00 00  22 80 00 00
0190  4d 80 00 00  04 00 00 00  00 00 00 00  00 00 00 00
01A0  4e 80 00 00  10 6d 02 00  00 00 00 00  00 00 00 00
01B0  4f 80 00 00  ec 23 00 00  00 00 00 00  00 00 00 00
01C0  62 80 00 00  38 78 02 00  00 00 00 00  22 01 00 00
01D0  6d 80 00 00  34 78 02 00  00 00 00 00  00 00 00 00
01E0  6e 80 00 00  08 00 00 00  00 00 00 00  00 00 00 00
01F0  10 1f 10 00  81 81 a0 9a  ae 1e 02 00  89 44 6a 0f

01f0  itemCount       [1 byte]  0x10       in this case
01f1  maxItemCount    [1 byte]  0x1f       constant
01f2  itemSize        [1 byte]  0x10       constant
01f3  nodeLevel       [1 byte]  0x00       in this case
01f8  backPointer     [4 bytes] 0x021eae   in this case

The itemCount specifies the number of 16 byte records that are active. The nodeLevel is zero for these leaf nodes. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a tuple of (D_ID, DESC-I_ID, TREE-I_ID, PARENT-D_ID) The DESC-I_ID points to the main data for this item (Associated Descriptor Items 0x7cec, 0xbcec, or 0x0101) via the index1 tree. The TREE-I_ID is zero or points to an Associated Tree Item 0x0002 via the index1 tree. The PARENT-D_ID points to the parent of this item in this index2 tree.

64 bit Index 2 Leaf Node

The 64 bit index2 b-tree leaf nodes are 512 byte blocks with the following format.

0000  21 00 00 00 00 00 00 00  74 00 00 00 00 00 00 00
0010  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0020  61 00 00 00 00 00 00 00  34 00 00 00 00 00 00 00
0030  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0040  22 01 00 00 00 00 00 00  4c 00 00 00 00 00 00 00
0050  00 00 00 00 00 00 00 00  22 01 00 00 02 00 00 00
0060  2d 01 00 00 00 00 00 00  70 00 00 00 00 00 00 00
0070  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0080  2e 01 00 00 00 00 00 00  08 00 00 00 00 00 00 00
0090  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
00A0  2f 01 00 00 00 00 00 00  0c 00 00 00 00 00 00 00
00B0  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
00C0  e1 01 00 00 00 00 00 00  00 00 00 00 00 00 00 00
00D0  00 00 00 00 00 00 00 00  00 00 00 00 d8 e3 13 00
00E0  01 02 00 00 00 00 00 00  8c 00 00 00 00 00 00 00
00F0  00 00 00 00 00 00 00 00  00 00 00 00 b0 e3 13 00
0100  61 02 00 00 00 00 00 00  00 00 00 00 00 00 00 00
0110  00 00 00 00 00 00 00 00  00 00 00 00 d8 e3 13 00
0120  0d 06 00 00 00 00 00 00  04 00 00 00 00 00 00 00
0130  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0140  0e 06 00 00 00 00 00 00  08 00 00 00 00 00 00 00
0150  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0160  0f 06 00 00 00 00 00 00  0c 00 00 00 00 00 00 00
0170  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
0180  10 06 00 00 00 00 00 00  10 00 00 00 00 00 00 00
0190  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
01A0  2b 06 00 00 00 00 00 00  24 00 00 00 00 00 00 00
01B0  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
01C0  71 06 00 00 00 00 00 00  18 00 00 00 00 00 00 00
01D0  00 00 00 00 00 00 00 00  00 00 00 00 02 00 00 00
01E0  00 00 00 00 00 00 00 00  0e 0f 20 00 00 00 00 00
01F0  81 81 77 56 f8 32 43 49  77 00 00 00 00 00 00 00

01e8  itemCount       [1 byte]  0x0e       in this case
01e9  maxItemCount    [1 byte]  0x0f       constant
01ea  itemSize        [1 byte]  0x20       constant
01eb  nodeLevel       [1 byte]  0x00       defines a leaf node
01f8  backPointer     [8 bytes] 0x000077   in this case

The itemCount specifies the number of 32 byte records that are active. The nodeLevel is zero for these leaf nodes. The backPointer must match the backPointer from the triple that pointed to this node.

Each item in this node is a tuple of (D_ID, DESC-I_ID, TREE-I_ID, PARENT-D_ID) The DESC-I_ID points to the main data for this item (Associated Descriptor Items 0x7cec, 0xbcec, or 0x0101) via the index1 tree. The TREE-I_ID is zero or points to an Associated Tree Item 0x0002 via the index1 tree. The PARENT-D_ID points to the parent of this item in this index2 tree.

32 bit Associated Tree Item 0x0002

A D_ID value may point to an entry in the index2 tree with a non-zero TREE-I_ID which points to this descriptor block via the index1 tree. It maps local ID2 values (referenced in the main data for the original D_ID item) to I_ID values. This descriptor block contains triples of (ID2, I_ID, CHILD-I_ID) where the local ID2 data can be found via I_ID, and CHILD-I_ID is either zero or it points to another Associated Tree Item via the index1 tree.

In the above 32 bit leaf node, we have a tuple of (0x61, 0x02a82c, 0x02a836, 0) 0x02a836 is the I_ID of the associated tree, and we can lookup that I_ID value in the index1 b-tree to find the (offset,size) of the data in the .pst file.

0000  02 00  01 00  9f 81 00 00  30 a8 02 00  00 00 00 00

0000  signature       [2 bytes] 0x0002     constant
0002  count           [2 bytes] 0x0001     in this case
  repeating
0004  id2             [4 bytes] 0x00819f   in this case
0008  i_id            [4 bytes] 0x02a830   in this case
000c  child-i_id      [4 bytes] 0          in this case

64 bit Associated Tree Item 0x0002

This descriptor block contains a tree that maps local ID2 values to I_ID entries, similar to the 32 bit version described above.

0000  02 00 02 00  00 00 00 00  92 06 00 00  00 00 00 00
0010  a8 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00
0020  3f 80 00 00  00 00 00 00  98 00 00 00  00 00 00 00
0030  00 00 00 00  00 00 00 00

0000  signature       [2 bytes] 0x0002     constant
0002  count           [2 bytes] 0x0002     in this case
0004  unknown         [4 bytes] 0          possibly constant
  repeating
0008  id2             [4 bytes] 0x000692   in this case
000c  unknown1        [2 bytes] 0          may be a count or size
000e  unknown2        [2 bytes] 0          may be a count or size
0010  i_id            [8 bytes] 0x0000a8   in this case
0018  child-i_id      [8 bytes] 0          in this case

Associated Descriptor Item 0xbcec

Contains information about the item, which may be email, contact, or other outlook types. In the above leaf node, we have a tuple of (0x21, 0x00e638, 0, 0) 0x00e638 is the I_ID of the associated descriptor, and we can lookup that I_ID value in the index1 b-tree to find the (offset,size) of the data in the .pst file. This descriptor is eventually decoded to a list of MAPI elements.

0000  3c 01 ec bc  20 00 00 00  00 00 00 00  b5 02 06 00
0010  40 00 00 00  f9 0f 02 01  60 00 00 00  01 30 1e 00
0020  80 00 00 00  04 30 1e 00  00 00 00 00  df 35 03 00
0030  ff 00 00 00  e0 35 02 01  a0 00 00 00  e2 35 02 01
0040  e0 00 00 00  e3 35 02 01  c0 00 00 00  e4 35 02 01
0050  00 01 00 00  e5 35 02 01  20 01 00 00  e6 35 02 01
0060  40 01 00 00  e7 35 02 01  60 01 00 00  1e 66 0b 00
0070  00 00 00 00  ff 67 03 00  00 00 00 00  d2 7f 17 d8
0080  64 8c d5 11  83 24 00 50  04 86 95 45  53 74 61 6e
0090  6c 65 79 00  00 00 00 d2  7f 17 d8 64  8c d5 11 83
00A0  24 00 50 04  86 95 45 22  80 00 00 00  00 00 00 d2
00B0  7f 17 d8 64  8c d5 11 83  24 00 50 04  86 95 45 42
00C0  80 00 00 00  00 00 00 d2  7f 17 d8 64  8c d5 11 83
00D0  24 00 50 04  86 95 45 a2  80 00 00 00  00 00 00 d2
00E0  7f 17 d8 64  8c d5 11 83  24 00 50 04  86 95 45 c2
00F0  80 00 00 00  00 00 00 d2  7f 17 d8 64  8c d5 11 83
0100  24 00 50 04  86 95 45 e2  80 00 00 00  00 00 00 d2
0110  7f 17 d8 64  8c d5 11 83  24 00 50 04  86 95 45 02
0120  81 00 00 00  00 00 00 d2  7f 17 d8 64  8c d5 11 83
0130  24 00 50 04  86 95 45 62  80 00 00 00  0b 00 00 00
0140  0c 00 14 00  7c 00 8c 00  93 00 ab 00  c3 00 db 00
0150  f3 00 0b 01  23 01 3b 01

0000  indexOffset     [2 bytes] 0x013c     in this case
0002  signature       [2 bytes] 0xbcec     constant
0004  b5offset        [4 bytes] 0x0020     index reference

Note the signature of 0xbcec. There are other descriptor block formats with other signatures. Note the indexOffset of 0x013c - starting at that position in the descriptor block, we have an array of two byte integers. The first integer (0x000b) is a (count-1) of the number of overlapping pairs following the count. The first pair is (0, 0xc), the next pair is (0xc, 0x14) and the last (12th) pair is (0x123, 0x13b). These pairs are (start,end+1) offsets of items in this block. So we have count+2 integers following the count value.

Note the b5offset of 0x0020, which is a type that I will call an index reference. Such index references have at least two different forms, and may point to data either in this block, or in some other block. External pointer references have the low order 4 bits all set, and are ID2 values that can be used to fetch data. This value of 0x0020 is an internal pointer reference, which needs to be right shifted by 4 bits to become 0x0002, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0xc, 0x14) pair.

So far we have only described internal index references where the high order 16 bits are zero. That suffices for single descriptor blocks. But in the case of the type 0x0101 descriptor block, we have an array of subblocks. In this case, the high order 16 bits of an internal index reference are used to select the subblock. Each subblock starts with a 16 bit indexOffset which points to the count and array of 16 bit integer pairs which are offsets in the current subblock.

Finally, we have the offset and size of the "b5" block located at offset 0xc with a size of 8 bytes in this descriptor block. The "b5" block has the following format:

0000  signature       [2 bytes] 0x02b5     constant
0002  datasize        [2 bytes] 0x0006     constant +2 for 8 byte entries
0004  descoffset      [4 bytes] 0x0040     index reference

Note the descoffset of 0x0040, which again is an index reference. In this case, it is an internal pointer reference, which needs to be right shifted by 4 bits to become 0x0004, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0x14, 0x7c) pair. The datasize (6) plus the b5 code (02) gives the size of the entries, in this case 8 bytes. We now have the offset 0x14 of the descriptor array, composed of 8 byte entries that describe MAPI elements. Each descriptor entry has the following format:

0000  itemType        [2 bytes]
0002  referenceType   [2 bytes]
0004  value           [4 bytes]

For some reference types (2, 3, 0xb) the value is used directly. Otherwise, the value is an index reference, which is either an ID2 value, or an offset, to be right shifted by 4 bits and used to fetch a pair from the index table to find the offset and size of the item in this descriptor block.

The following reference types are known, but not all of these are implemented in the code yet.

0x0002 - Signed 16bit value
0x0003 - Signed 32bit value
0x0004 - 4-byte floating point
0x0005 - Floating point double
0x0006 - Signed 64-bit int
0x0007 - Application Time
0x000A - 32-bit error value
0x000B - Boolean (non-zero = true)
0x000D - Embedded Object
0x0014 - 8-byte signed integer (64-bit)
0x001E - Null terminated String
0x001F - Unicode string
0x0040 - Systime - Filetime structure
0x0048 - OLE Guid
0x0102 - Binary data
0x1003 - Array of 32bit values
0x1014 - Array of 64bit values
0x101E - Array of Strings
0x1102 - Array of Binary data

The following item types are known, but not all of these are implemented in the code yet.

0x0002  Alternate recipient allowed
0x0003  Extended Attributes Table
0x0017  Importance Level
0x001a  IPM Context, message class
0x0023  Global delivery report requested
0x0026  Priority
0x0029  Read Receipt
0x002b  Reassignment Prohibited
0x002e  Original Sensitivity
0x0032  Report time
0x0036  Sensitivity
0x0037  Email Subject
0x0039  Client submit time / date sent
0x003b  Outlook Address of Sender
0x003f  Outlook structure describing the recipient
0x0040  Name of the Outlook recipient structure
0x0041  Outlook structure describing the sender
0x0042  Name of the Outlook sender structure
0x0043  Another structure describing the recipient
0x0044  Name of the second recipient structure
0x004f  Reply-To Outlook Structure
0x0050  Name of the Reply-To structure
0x0051  Outlook Name of recipient
0x0052  Second Outlook name of recipient
0x0057  My address in TO field
0x0058  My address in CC field
0x0059  Message addressed to me
0x0063  Response requested
0x0064  Sender's Address access method (SMTP, EX)
0x0065  Sender's Address
0x0070  Conversation topic, processed subject (with Fwd:, Re, ... removed)
0x0071  Conversation index
0x0072  Original display BCC
0x0073  Original display CC
0x0074  Original display TO
0x0075  Recipient Address Access Method (SMTP, EX)
0x0076  Recipient's Address
0x0077  Second Recipient Access Method (SMTP, EX)
0x0078  Second Recipient Address
0x007d  Email Header. This is the header that was attached to the email
0x0c04  NDR Reason code
0x0c05  NDR Diag code
0x0c06  Non-receipt notification requested
0x0c17  Reply Requested
0x0c19  Second sender structure
0x0c1a  Name of second sender structure
0x0c1b  Supplementary info
0x0c1d  Second outlook name of sender
0x0c1e  Second sender access method (SMTP, EX)
0x0c1f  Second Sender Address
0x0c20  NDR status code
0x0e01  Delete after submit
0x0e02  BCC Addresses
0x0e03  CC Addresses
0x0e04  SentTo Address
0x0e06  Date.
0x0e07  Flag bits
            0x01 - Read
            0x02 - Unmodified
            0x04 - Submit
            0x08 - Unsent
            0x10 - Has Attachments
            0x20 - From Me
            0x40 - Associated
            0x80 - Resend
            0x100 - RN Pending
            0x200 - NRN Pending
0x0e08  Message Size
0x0e0a  Sentmail EntryID
0x0e1f  Compressed RTF in Sync
0x0e20  Attachment Size
0x0ff9  binary record header
0x1000  Plain Text Email Body. Does not exist if the email doesn't have a plain text version
0x1001  Report Text
0x1006  RTF Sync Body CRC
0x1007  RTF Sync Body character count
0x1008  RTF Sync body tag
0x1009  RTF Compressed body
0x1010  RTF whitespace prefix count
0x1011  RTF whitespace tailing count
0x1013  HTML Email Body. Does not exist if the email doesn't have an HTML version
0x1035  Message ID
0x1042  In-Reply-To or Parent's Message ID
0x1046  Return Path
0x3001  Folder Name? I have seen this value used for the contacts record aswell
0x3002  Address Type
0x3003  Contact Address
0x3004  Comment
0x3007  Date item creation
0x3008  Date item modification
0x300b  binary record header
0x35df  Valid Folder Mask
0x35e0  binary record contains a reference to "Top of Personal Folder" item
0x35e2  binary record contains a reference to default outbox item
0x35e3  binary record contains a reference to "Deleted Items" item
0x35e4  binary record contains a reference to sent items folder item
0x35e5  binary record contains a reference to user views folder item
0x35e6  binary record contains a reference to common views folder item
0x35e7  binary record contains a reference to "Search Root" item
0x3602  the number of emails stored in a folder
0x3603  the number of unread emails in a folder
0x360a  Has Subfolders
0x3613  the folder content description
0x3617  Associate Content count
0x3701  Binary Data attachment
0x3704  Attachment Filename
0x3705  Attachement method
0x3707  Attachment Filename long
0x370b  Attachment Position
0x370e  Attachment mime encoding
0x3710  Attachment mime Sequence
0x3a00  Contact's Account name
0x3a01  Contact Alternate Recipient
0x3a02  Callback telephone number
0x3a03  Message Conversion Prohibited
0x3a05  Contacts Suffix
0x3a06  Contacts First Name
0x3a07  Contacts Government ID Number
0x3a08  Business Telephone Number
0x3a09  Home Telephone Number
0x3a0a  Contacts Initials
0x3a0b  Keyword
0x3a0c  Contact's Language
0x3a0d  Contact's Location
0x3a0e  Mail Permission
0x3a0f  MHS Common Name
0x3a10  Organizational ID #
0x3a11  Contacts Surname
0x3a12  original entry id
0x3a13  original display name
0x3a14  original search key
0x3a15  Default Postal Address
0x3a16  Company Name
0x3a17  Job Title
0x3a18  Department Name
0x3a19  Office Location
0x3a1a  Primary Telephone
0x3a1b  Business Phone Number 2
0x3a1c  Mobile Phone Number
0x3a1d  Radio Phone Number
0x3a1e  Car Phone Number
0x3a1f  Other Phone Number
0x3a20  Transmittable Display Name
0x3a21  Pager Phone Number
0x3a22  user certificate
0x3a23  Primary Fax Number
0x3a24  Business Fax Number
0x3a25  Home Fax Number
0x3a26  Business Address Country
0x3a27  Business Address City
0x3a28  Business Address State
0x3a29  Business Address Street
0x3a2a  Business Postal Code
0x3a2b  Business PO Box
0x3a2c  Telex Number
0x3a2d  ISDN Number
0x3a2e  Assistant Phone Number
0x3a2f  Home Phone 2
0x3a30  Assistant's Name
0x3a40  Can receive Rich Text
0x3a41  Wedding Anniversary
0x3a42  Birthday
0x3a43  Hobbies
0x3a44  Middle Name
0x3a45  Display Name Prefix (Title)
0x3a46  Profession
0x3a47  Preferred By Name
0x3a48  Spouse's Name
0x3a49  Computer Network Name
0x3a4a  Customer ID
0x3a4b  TTY/TDD Phone
0x3a4c  Ftp Site
0x3a4d  Gender
0x3a4e  Manager's Name
0x3a4f  Nickname
0x3a50  Personal Home Page
0x3a51  Business Home Page
0x3a57  Company Main Phone
0x3a58  childrens names
0x3a59  Home Address City
0x3a5a  Home Address Country
0x3a5b  Home Address Postal Code
0x3a5c  Home Address State or Province
0x3a5d  Home Address Street
0x3a5e  Home Address Post Office Box
0x3a5f  Other Address City
0x3a60  Other Address Country
0x3a61  Other Address Postal Code
0x3a62  Other Address State
0x3a63  Other Address Street
0x3a64  Other Address Post Office box
0x3fde  Internet code page
0x3ffd  Message code page
0x65e3  Entry ID
0x67f2  Attachment ID2 value
0x67ff  Password checksum
0x6f02  Secure HTML Body
0x6f04  Secure Text Body
0x7c07  Top of folders RecID
0x8005  Contact Fullname
0x801a  Home Address
0x801b  Business Address
0x801c  Other Address
0x8045  Work Address Street
0x8046  Work Address City
0x8047  Work Address State
0x8048  Work Address Postal Code
0x8049  Work Address Country
0x804a  Work Address Post Office Box
0x8082  Email Address 1 Transport
0x8083  Email Address 1 Address
0x8084  Email Address 1 Description
0x8085  Email Address 1 Record
0x8092  Email Address 2 Transport
0x8093  Email Address 2 Address
0x8094  Email Address 2 Description
0x8095  Email Address 2 Record
0x80a2  Email Address 3 Transport
0x80a3  Email Address 3 Address
0x80a4  Email Address 3 Description
0x80a5  Email Address 3 Record
0x80d8  Internet Free/Busy
0x8205  Appointment shows as
0x8208  Appointment Location
0x820d  Appointment start
0x820e  Appointment end
0x8214  Label for appointment
0x8215  All day appointment flag
0x8216  Appointment recurrence data
0x8223  Appointment is recurring
0x8231  Recurrence type
0x8232  Recurrence description
0x8234  TimeZone of times
0x8235  Recurrence Start Time
0x8236  Recurrence End Time
0x8501  Reminder minutes before appointment start
0x8503  Reminder alarm
0x8516  Common Time Start
0x8517  Common Time End
0x851f  Play reminder sound filename
0x8530  Followup String
0x8534  Mileage
0x8535  Billing Information
0x8554  Outlook Version
0x8560  Appointment Reminder Time
0x8700  Journal Entry Type
0x8706  Start Timestamp
0x8708  End Timestamp
0x8712  Journal Entry Type - duplicate?

Associated Descriptor Item 0x7cec

This style of descriptor block is similar to the 0xbcec format. This descriptor is also eventually decoded to a list of MAPI elements.

0000  7a 01 ec 7c  40 00 00 00  00 00 00 00  b5 04 02 00
0010  60 00 00 00  7c 18 60 00  60 00 62 00  65 00 20 00
0020  00 00 80 00  00 00 00 00  00 00 03 00  20 0e 0c 00
0030  04 03 1e 00  01 30 2c 00  04 0b 1e 00  03 37 28 00
0040  04 0a 1e 00  04 37 14 00  04 05 03 00  05 37 10 00
0050  04 04 1e 00  07 37 24 00  04 09 1e 00  08 37 20 00
0060  04 08 02 01  0a 37 18 00  04 06 03 00  0b 37 08 00
0070  04 02 1e 00  0d 37 1c 00  04 07 1e 00  0e 37 40 00
0080  04 10 02 01  0f 37 30 00  04 0c 1e 00  11 37 34 00
0090  04 0d 1e 00  12 37 3c 00  04 0f 1e 00  13 37 38 00
00A0  04 0e 03 00  f2 67 00 00  04 00 03 00  f3 67 04 00
00B0  04 01 03 00  09 69 44 00  04 11 03 00  fa 7f 5c 00
00C0  04 15 40 00  fb 7f 4c 00  08 13 40 00  fc 7f 54 00
00D0  08 14 03 00  fd 7f 48 00  04 12 0b 00  fe 7f 60 00
00E0  01 16 0b 00  ff 7f 61 00  01 17 45 82  00 00 00 00
00F0  45 82 00 00  78 3c 00 00  ff ff ff ff  49 1e 00 00
0100  06 00 00 00  00 00 00 00  a0 00 00 00  00 00 00 00
0110  00 00 00 00  00 00 00 00  00 00 00 00  c0 00 00 00
0120  00 00 00 00  00 00 00 00  00 00 00 00  00 00 00 00
0130  00 00 00 00  00 00 00 00  00 00 00 00  00 40 dd a3
0140  57 45 b3 0c  00 40 dd a3  57 45 b3 0c  02 00 00 00
0150  00 00 fa 10  3e 2a 86 48  86 f7 14 03  0a 03 02 01
0160  4a 2e 20 44  61 76 69 64  20 4b 61 72  61 6d 27 73
0170  20 42 69 72  74 68 64 61  79 00 06 00  00 00 0c 00
0180  14 00 ea 00  f0 00 55 01  60 01 79 01

0000  indexOffset     [2 bytes] 0x017a     in this case
0002  signature       [2 bytes] 0x7cec     constant
0004  7coffset        [4 bytes] 0x0040     index reference

Note the signature of 0x7cec. There are other descriptor block formats with other signatures. Note the indexOffset of 0x017a - starting at that position in the descriptor block, we have an array of two byte integers. The first integer (0x0006) is a (count-1) of the number of overlapping pairs following the count. The first pair is (0, 0xc), the next pair is (0xc, 0x14) and the last (7th) pair is (0x160, 0x179). These pairs are (start,end+1) offsets of items in this block. So we have count+2 integers following the count value.

Note the 7coffset of 0x0040, which is an index reference. In this case, it is an internal reference pointer, which needs to be right shifted by 4 bits to become 0x0004, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0x14, 0xea) pair. We have the offset and size of the "7c" block located at offset 0x14 with a size of 214 bytes in this case. The "7c" block starts with a header with the following format:

0000  signature       [1 bytes] 0x7c       constant
0001  itemCount       [1 bytes] 0x18       in this case
0002  unknown         [2 bytes] 0x0060     in this case
0004  unknown         [2 bytes] 0x0060     in this case
0006  unknown         [2 bytes] 0x0062     in this case
0008  recordSize      [2 bytes] 0x0065     in this case
000a  b5Offset        [4 bytes] 0x0020     index reference
000e  index2Offset    [4 bytes] 0x0080     index reference
0012  unknown         [2 bytes] 0x0000     in this case
0014  unknown         [2 bytes] 0x0000     in this case

Note the b5Offset of 0x0020, which is an index reference. In this case, it is an internal reference pointer, which needs to be right shifted by 4 bits to become 0x0002, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0xc, 0x14) pair. Finally, we have the offset and size of the "b5" block located at offset 0xc with a size of 8 bytes in this descriptor block. The "b5" block has the following format:

0000  signature       [2 bytes] 0x04b5     constant
0002  datasize        [2 bytes] 0x0002     +4 for 6 byte entries in this case
0004  descoffset      [4 bytes] 0x0060     index reference

Note the descoffset of 0x0060, which again is an index reference. In this case, it is an internal pointer reference, which needs to be right shifted by 4 bits to become 0x0006, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0xea, 0xf0) pair. The datasize (2) plus the b5 code (04) gives the size of the entries, in this case 6 bytes. We now have the offset 0xea of an unused block of data in an unknown format, composed of 6 byte entries. That gives us (0xf0 - 0xea)/6 = 1, so we have a recordCount of one.

We have seen cases where the descoffset in the b5 block is zero, and the index2Offset in the 7c block is zero. This has been seen for objects that seem to be attachments on messages that have been read. Before the message was read, it did not have any attachments.

Note the index2Offset above of 0x0080, which again is an index reference. In this case, it is an internal pointer reference, which needs to be right shifted by 4 bits to become 0x0008, which is then a byte offset to be added to the above indexOffset plus two (to skip the count), so it points to the (0xf0, 0x155) pair. This is an array of tables of four byte integers. We will call these the IND2 tables. The size of each of these tables is specified by the recordSize field of the "7c" header. The number of these tables is the above recordCount value derived from the "b5" block.

Now the remaining data in the "7c" block after the header starts at offset 0x2a. There should be itemCount 8 byte items here, with the following format:

0000  referenceType   [2 bytes]
0002  itemType        [2 bytes]
0004  ind2Offset      [2 bytes]
0006  size            [1 byte]
0007  unknown         [1 byte]

The ind2Offset is a byte offset into the current IND2 table of some value. If that is a four byte integer value, then once we fetch that, we have the same triple (item type, reference type, value) as we find in the 0xbcec style descriptor blocks. If not, then this value is used directly. These 8 byte descriptors are processed recordCount times, each time using the next IND2 table. The item and reference types are as described above for the 0xbcec format descriptor block.

32 bit Associated Descriptor Item 0x0101

This descriptor block contains a list of I_ID values. It is used when an I_ID (that would normally point to a type 0x7cec or 0xbcec descriptor block) contains more data than can fit in any single descriptor of those types. In this case, it points to a type 0x0101 block, which contains a list of I_ID values that themselves point to the actual descriptor blocks. The total length value in the 0x0101 header is the sum of the lengths of the blocks pointed to by the list of I_ID values. The result is an array of subblocks, that may contain index references where the high order 16 bits specify which descriptor subblock to use. Only the first descriptor subblock contains the signature (0xbcec or 0x7cec).

0000  01 01 02 00  26 28 00 00  18 77 0c 00  b8 04 00 00

0000  signature       [2 bytes] 0x0101     constant
0002  count           [2 bytes] 0x0002     in this case
0004  total length    [4 bytes] 0x002826   in this case
  repeating
0008  i_id            [4 bytes] 0x0c7718   in this case
000c  i_id            [4 bytes] 0x0004b8   in this case

64 bit Associated Descriptor Item 0x0101

This descriptor block contains a list of I_ID values, similar to the 32 bit version described above.

0000  01 01 02 00  ea 29 00 00  10 83 00 00  00 00 00 00
0010  1c 83 00 00  00 00 00 00

0000  signature       [2 bytes] 0x0101     constant
0002  count           [2 bytes] 0x0002     in this case
0004  total length    [4 bytes] 0x0029ea   in this case
  repeating
0008  i_id            [8 bytes] 0x008310   in this case
0010  i_id            [8 bytes] 0x00831c   in this case