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There's a file called MM! in every directory in DOS 6.22. Just MM!, no file extension... What causes this?

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I'll take "Computer Viruses" for $200, Alex. – msw Jul 5 '10 at 23:23
I agree with msw here. There is no documented reason for this behaviour. – Breakthrough Feb 22 '11 at 21:18
I didn't know DOS 6.22 even existed any more. – HK1 Mar 3 '11 at 21:34
HK1: Most people have upgraded to FreeDOS: – Randolf Richardson Mar 6 '11 at 17:53
Can you examine the contents of one of these MM! files? – Majenko Mar 13 '11 at 12:48

If your DOS 6.22 system has network file-sharing enabled and it's file-shares are accessed from a Windows system that is running some file management/cataloging software, it is possible the software creates the "MM!" files to keep track of some metadata such as the archiving policies for each folder or a history of actions taken.

This is pure speculation based on Googling for "MM file", noting certain interesting results and thinking about the way products like Picasa (not the culprit) create metatdata files in each folder.

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