Windows 7 Instability - AVG problem?

Yesterday, my wife's Windows 7 PC started behaving erratically, taking ages to load and not allowing her to "do" anything when she finally got to the desktop. When I tried to resolve the problem I started getting random reboots and a number of blue screens (eg 0xF4, then a registry error among others). I even had problems getting into Safe mode. At first I suspected hardware, but I have lost count of the number of times I have been drawn to this conclusion before (I maintain/repair Pcs) but eventually finding a hidden software issue to be at the heart of the problem.

Today I seemed to get stuck on the loading Windows 7 screen and could get no further and I noticed that Safe mode seemed to be getting stuck loading the second of the AVG drivers (sorry I don't recall the name).

After attempting a repair (which didn't work) I manged to get into safe mode and uninstalled AVG using the Uninstall tool from AVG's website (the uninstaller would not work in Safe mode).

Fingers crossed, it now seems to be working. I think I'll give Avast a try!

 

I recommend program called "WhoCrashed" by Resplendence to help track down what is causing your BSODs. It searches through mini, kernel, and/or full memory dump files that are written when Windows shuts down.

I've never seen an antivirus program cause a BSOD myself, but I suppose that it could be trying to access protected memory during realtime monitoring and thus cause a violation. This is just speculation however.

 

0xF4 bugchecks are frequently hard drive/SSD -related. If it has an SSD especially, check for firmware updates.

Otherwise use SeaTools or the brand-specific test tools for the drive from a bootable USB and, if it comes up clear, run chkdsk C: /r /f and let Windows check for/fix errors.