Compress v 1.02 and 1.11 will create KWAJ files. These date from 1990 (the WLO10.ZIP file for OS/2 is compressed in these). It's used in DOS 6, and Windows 3.11, it's hard to find. Vers 1.11 is the go, because the default rename is to edlin.ex_ rather than edlin.ex$. I got 1.02 from the fox pro 2.6 redistribution, and 1.11 in the msdos 6 source code package. Compress v2.0 is available in the Windows 3.1 SDK and many other things, that produce SZDD files. The compress in the Windows NT 3.10 reskit produces this file. Compress v2.5 in the resource kits, etc, by default, produce MSCF files (MSZIP), with varying degrees of compression. Look for CABPACK v 1.1 for a DOS version of this. Expand 2.1 (windows 3.11), expands both KWAJ and SZDD, but not MSCF. Other expand utilities work with some subset of SZDD, KWAJ and MSCF. The DIAMOND utility even in the earliest packages, are Win32. You could look for cabpack 1.1 for a DOS version. Needs to have the Runtime 200 fix applied, though.