Computer crashes during anti virus scan

Every time I run an AVG anti virus scan (scheduled or manual), my system crashes. I have not noticed any symptoms other than that, but I suspect that my computer is infected with something.
I am running WinXP SP3 on a Dell Dimension 9100 with a 3GHz processor and 2GB of RAM (160GB HD with 89GB free space).

Any help would be greatly appreciated.

Thanks,
Sacha

Hello korell
Lets have a look with this and see what's going on http://www.malwarebytes.org/mbam.php
Some types of malware will disable MBAM (MalwareBytes) and other security tools. If MBAM will not install, try renaming it.

Before saving any of your security programs, rename them first. For example, before you save Malwarebytes', rename it to something like MBblah.exe and then click on Save and save it to your desktop. Same thing after you install it. Before running it, rename the main executable file first
***
Right-click on the mbam-setup.exe file and change the .exe extension to .bat, .com, .pif, or .scr and then double-click on it to run.

If after installation, MBAM will not run, open the Malwarebytes' Anti-Malware folder in Program Files, right-click on mbam.exe and change the .exe as noted above. Then double-click on it to run..

***
Open up command prompt, type in following commands:
XP >> click the Start menu at the lower-left of your computer's desktop and select "Run". Type cmd into the Run box and click "OK".
Vista >> click the Start menu at the lower-left of your computer's desktop and Type cmd in the search box.

regsvr32 mbamext.dll
regsvr32 ssubtmr6.dll
regsvr32 vbalsgrid6.ocx
regsvr32 zlib.dll

***

Try using a System Retore Point prior to the date of infection. You may be able to update and run MBam. Note this did not remove the malware.
Windows XP System Restore Guide

[credits to boopme]

D_N_M

Thanks for your quick reply, D_N_M!

I ran MBAM and had the same symptom. About 30 minutes into the scan, the system crashed. I then restarted and ran MBAM again. This time I monitored it as it got closer to the 30 minute mark. At 31 min 12 sec it crashed again, but I was able to see where in the scan process it happened. The scan process stopped at "C:\Program Files\Microsoft Office\OFFICE11\VS Runtime\MSENV.DLL". I then restarted yet once again and scanned just that file by itself and it came back clean. I then scanned all the remaining files except the one following MSENV.DLL as I expected it to be the cuplrit. All other files in the "VS Runtime" directory scanned clean. I then tried to scan MSVCP70.DLL (the one following MSENV.DLL), and the system immediately crashed. After restart I tried to just select that file and it crashed again. It appears that every attempt to access MSVCP70.DLL causes the system to crash.

Any ideas what to do now?

Thanks,
Sacha

Any other suggestions?!?!

Thanks,
Sacha

Receiving assistance here: http://www.bleepingcomputer.com/forums/t/265030/system-crash-during-anti-virus-scan/

Topic closed.

~ OB