I didn't do a search on this particular stop error, but it often seems that 
these failure to boot problems are the result of corrupted files.  Can you 
get into the BIOS or Setup menu and change the device boot order there?  If 
so, perhaps you can try running chkdsk from the windows xp install disk, or 
Spinrite, if you have that available.  However, since the assumption that we 
are dealing with corrupted files makes me wonder about a failing hard drive, 
it probably would be a good precaution to back up the data on this hard 
drive to another one before doing this file maintenance.  You'll have to 
pull the drive from the laptop and use something like a USB external caddy 
to do this.  (This would allow you to run chkdsk from another computer on 
the drive, as well.)

See if anyone else has any thoughts on this.  The only worry I have about 
this advice is that I seem to recall running into some version of windows 
"marking" a drive as an external drive, somehow, and this leading to 
problems when I tried to reinstall windows on it.  I wish my fuzzy memory 
would allow me to be more specific about whatever this was that I ran into. 
I'm thinking that I was trying to put the windows install files on a second 
partition via an external drive connection, but I was unable to run them 
when I put the drive back into a computer, because windows wouldn't install 
to what it thought was still an external drive.  (I think that I was working 
with an older laptop with a failed optical drive.)  All this is probably 
irrelevant to what you are trying to do.

John Sproule

Date:    Wed, 6 Oct 2010 19:23:19 +0000
From:    "Hachmeyer, Mr. Paul S." <[log in to unmask]>
Subject: xp bsod STOP:  c000021a (fatal system error)

A friend brought me his Dell Latitude D610 laptop which gets this error when 
booting.  I can't get into safe mode or any other option, whichever I 
select, once it starts xp, it craps out.  If I try to select another boot 
device, I can't get to the cd drive selection, seems like his 'down' key is 
broken, and the 'up' key doesn't wrap to the bottom of the boot selection 
list.  Options on the web suggest reinstalling or repairing xp, but I can't 
get the cd drive selected.
I'm not sure what sp is installed, can't get in to check that.  Seems to 
have been a few os program glitches over the years with xp that might cause 
this message.  There is no Norton or Symantec software installed (backup 
apparently was another problem causing this message), and the memory chip 
was popped out and replaced, since sometimes that causes the error.
Any ideas?
Paul Hachmeyer

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