Windows 9x supported long filenames by overriding DOS instruction to provide it, so they only worked while Windows was running. If you rebooted the PC in MS-DOS

Windows 9x supported long filenames by overriding DOS instruction to provide it, so they only worked while Windows was running. If you rebooted the PC in MS-DOS-only mode LFN wouldn't work. There were a bunch of TSRs that added support though. Here is one i used recently on a retro PC to install Free Pascal for DOS (which, despite being for DOS, requires long filename support to install - though depending on which units you use, it can work without it afterwards): http://adoxa.altervista.org/doslfn/ http://adoxa.altervista.org/doslfn/