Path: utzoo!attcan!uunet!ssbell!mcmi!unocss!ho@fergvax.unl.edu
From: ho@fergvax.unl.edu (Tiny Bubbles...)
Newsgroups: comp.sys.ibm.pc
Subject: Re: What does "Probable Non-DOS disk" mean?
Message-ID: <918@unocss..unl.edu>
Date: 12 Dec 89 00:13:29 GMT
References: <1598@dsac.dla.mil>
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From article <1598@dsac.dla.mil>, by nfs0294@dsac.dla.mil (Glendell R. Midkiff):
> From article <1989Dec7.123115.13255@aucs.uucp>, by peter@aucs.uucp (Peter Steele):
>> I went to do a chkdsk/f the other day and it reported that drive C
>> was a "probable non-DOS disk". It gave me the option of continuing
>> and I did and everything worked fine. What causes this error and
>> can it be removed. The machine is running DOS 3.3. No partitions
> 
> I also ran across this a couple weeks ago on a Epson Equity II running
> MS-DOS 3.3 with a Seagate ST238R/Ompti RLL controller.  Everything

Me too.  What happens is the 'media byte' in the first sector of the FAT
gets clobbered.  I've never quite figured out why.

I have a sneaking suspicion that, since lots of other people seem to have the 
problem, it is a bug in DOS which occasionally corrupts the media byte under
certain unusual conditions.  

I don't believe it's a random error, as there are just too many people who
have had it happen to them.  But I could be wrong!
---
	... Michael Ho, University of Nebraska
Internet: ho@hoss.unl.edu		USnail:  115 Nebraska Union
BITnet:   cosx001@UNLCDC3			 Lincoln, NE 68588-0461