Start to compress these files using makecab. Example: makecab C:\path\to\files\1.cab makecab C:\path\to\files\1.inf makecab C:\path\to\files\1.sys You should now have 3 new files: 1.ca_ 1.in_ 1.sy_ Copy these 3 files to your I386 directory. Now look for dosnet.inf in the I386 directory and open it with notepad. Add the files to [Files]: d1,1.cab d1,1.inf d1,1.sys Now look for txtsetup.sif and open it with notepad. Add the files to [sourceDisksFiles]. 1.cab = 1,,,,,,,2,0,0 1.inf = 1,,,,,,,2,0,0 1.sys = 1,,,,,,,2,0,0