As far as I remember, MS-DOS 4.0 was specifically made for the European/German Siemens corporation. Was some weird mix of DOS and the later DosShell (itself almost like the Windows 3.0 standard mode kernel). It provided Unix-like foreground and background processes, and so somehow resembled a multitasking environment.

RalfBrownsInterruptList has in-deep informations about this.

Just wondering, because someone said on TheTwelveSimpleSecretsOfMicrosoftManagement, that it was a big flop.

Yes, I was wondering about the flop part too. In Sweden we all had MS-DOS 4.01 (4.0 had some extremely stupid bug, going to look up what that was) until MS-DOS 5 came out. The DosShell was really cool. Used it quite often on computers lacking NortonCommander, when I wanted a file manager and didn't have the patience (or available lowmem...) to start Windows. Some installations even booted into DosShell, using it as a menu program. I seem to remember playing with some config files for that. --ClaesWallin
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