I have a co-worker's Dell Inspiron 6400 running XP Home and it was badly infected with several viruses and trojans. I removed the viruses by hooking up hard drive externally and ran several scans with malwarebytes, AVG, and superantispyware. I think all infections are removed, but I still receive BSOD with "Fatal System Error" c000021a right after windows boots up. Cannot get to logon screen, safe mode does not work, and last known good config doesn't work either. All options just lead to the same bsod. I have a windows xp pro cd and am wondering if it's possible to repair it from the recovery console. I am running chkdsk /r now from recovery console, but I think I have missing winlogon.exe and possibly more. Any help would be appreciated so I can get logged on this computer and make sure it's clean once and for all. Thanks.