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From: mjf@cunixb.cc.columbia.edu (Michael J Flory)
Newsgroups: comp.windows.ms
Subject: Strange memory errors in Windows?
Summary: Every other byte missing (E e y o h r b t   i s n )!
Message-ID: <1991May29.005554.10290@cunixf.cc.columbia.edu>
Date: 29 May 91 00:55:54 GMT
Sender: usenet@cunixf.cc.columbia.edu (The Network News)
Reply-To: mjf@cunixb.cc.columbia.edu (Michael J Flory)
Organization: Columbia University
Lines: 23
Nntp-Posting-Host: cunixb.cc.columbia.edu


Some time ago I posted with a strange and dangerous error I got running
DISKCOPY in a DOS window with a .pif asking for all 640 K if it could get
it.  In short, the diskcopy operation miscopied a couple of sectors every
dozen-and-a-half or so (the number varied).  But although VERIFY was on,
I got no error message -- I discovered it through DISKCOMP.

Now, running XTREE GOLD 2.0 under windows, I have discovered that the 
beginning parts of whole sets of files copied to a floppy are sometimes
trashed, and (as I recall -- one of the files trashed was my notes on the
other problem) these file-beginnings were trashed in the same way: every 
OTHER byte became FF, beginning with the 2nd byte.  The number of bytes
varied, but seemed always to end on a sector boundary.  It reminded me of
the way the version of DOS installed by OEM's when you don't buy a full
DOS would copy itself to a floppy -- every other byte zeroed!

I've tested the RAM in my machine, and my floppy drive seems reliable
(other files read and write fine).  Could Windows be misallocating memory
for DOS (3.30, by the way) and allowing something else to write over it?

Any help much appreciated.  I'm mystified.

Michael Flory (mjf@cunixb.cc.columbia.edu)