Microsoft KWAJ installation compression
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				|  (Split off from MS-DOS installation compression) | |||
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| == Identification == | == Identification == | ||
| − | + | Files begin with bytes {{magic|4b 57 41 4a 88 f0 27 d1}}. | |
| == Specifications == | == Specifications == | ||
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| == Software == | == Software == | ||
| − | |||
| * [https://archive.org/details/msdn-1996-04 MSDN Library - April 1996] → MSDN15_1.iso → MSDNSMPL/PROD/EISPAK11/DECOMP.EXE - Decompression utility for DOS; supports compression methods 2, 3, 4 | * [https://archive.org/details/msdn-1996-04 MSDN Library - April 1996] → MSDN15_1.iso → MSDNSMPL/PROD/EISPAK11/DECOMP.EXE - Decompression utility for DOS; supports compression methods 2, 3, 4 | ||
| + | * [https://www.cabextract.org.uk/libmspack/ libmspack] | ||
| + | * {{Deark}} | ||
| See also [[MS-DOS installation compression#Software]]. | See also [[MS-DOS installation compression#Software]]. | ||
| [[Category:Microsoft]] | [[Category:Microsoft]] | ||
| + | [[Category:MS-DOS]] | ||
Revision as of 16:29, 7 January 2023
Microsoft KWAJ installation compression refers to a compressed file format used for software installation by Microsoft and their installer tools. "KWAJ" refers to the signature bytes at the beginning of a compressed file.
KWAJ is a relative of some similar formats, most importantly the one known as "SZDD". For the other formats, see MS-DOS installation compression and Microsoft SZ installation compression.
KWAJ is more sophisticated than SZDD, though the relationship between them is not clear.
| Contents | 
Format details
There is a 16-bit field at offset 8 that specifies the compression or encoding method.
| Compression code | Description | 
|---|---|
| 0 | Uncompressed (rare) | 
| 1 | XOR (rare) | 
| 2 | Okumura's LZSS | 
| 3 | LZ77 + Huffman | 
| 4 | MSZIP (based on DEFLATE) | 
Identification
Files begin with bytes 4b 57 41 4a 88 f0 27 d1.
Specifications
Software
- MSDN Library - April 1996 → MSDN15_1.iso → MSDNSMPL/PROD/EISPAK11/DECOMP.EXE - Decompression utility for DOS; supports compression methods 2, 3, 4
- libmspack
- Deark
See also MS-DOS installation compression#Software.

