MS-DOS installation compression
From Just Solve the File Format Problem
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Revision as of 14:46, 2 June 2013
The MS-DOS installation compression system is used for system installation files when installing or upgrading MS-DOS starting with version 5.0a. It replaces the last character of the file extension with an underscore. The EXPAND command decompresses the files, and is run as part of the installer. Apparently the Google Chrome installation process also needs it.
This format (usually?) uses LZ77 compression.
Identification
File begin with bytes 53 5A 44 44 88 F0 27 33, or (rarely?) 4B 57 41 4A 88 F0 27 D1.
Software
- EXPAND.EXE - utility included with many versions of MS Windows and MS-DOS
- 7-Zip
- mscompress - msexpand
