AVG is corrupt....

This lady's laptop has continuing AVG problems. About every 30 or 40 days, her AVG gets corrupted and needs to be uninstalled and reinstalled. About half the time, it won't uninstall completely or successfully without errors. Over time, this has caused there to be several Grisoft folders in C:\Program Files. Finally, she told me about it, and I'm trying to do something about it. Apparently, she'd try to uninstall. If that didn't work, she'd rename the Grisoft folder to Grisoft1 or something, and reload the software. Obviously, not a great idea. So, just now, I reinstalled it 'clean' so I could uninstall it 'clean'. And it did uninstall OK. But now what? Do I go with a different AV app? There's still the 4 or 5 Grisoft folders in Program Files, and probably a bunch of messed up registry keys. Run CCleaner on the reg? Clean the leftover files and folders? Is there an AVG uninstaller like there is for Norton or MacAfee? And why does AVG keep getting corrupt? I've installed AVG ALOT of times on MANY different PCs, and never really had a problem like this. I've run other scans and found absolutely NO malware other than your basic cookies. So, what gives? Any ideas will be appreciated.
Thanks.

 

See if there are still uninstallers in the Grisoft AVG folders. If there are, see if you can still run them. If not delete the folders and run CCleaner' registry tool (or your favorite reg cleaner searching for only Grisoft) I am only familiar with RegSeeker and it has a find in registry option and I would assume most good reg cleaners do, too.
Does she have any other software by Grisoft? If she does and you use the reg cleaner option, make sure to manually inspect each entry to make sure it is what you want gone.
Then try a new install.
I don't know why AVG would go corrupt. Possibly something in her Windows files causing it to corrupt. Have you tried SFC yet to make sure Windows is intact? Have you made sure there is no malware in her system?
The AVG app on my wifes PC has been running great for close to two years with only the daily updates.

 

Yes to both questions. SFC completed as usual with no fanfare, nice and quiet. Same with the malware scans, nothing but a few cookies for 'casalemedia' and the like. I ran 3 different scans and found absolutely nothing besides the cookies. She's one of the few people who uses the web only for paying bills and taking online classes. And that's it, she doesn't really 'surf' like most of us, and therefore has a VERY clean (and safe) PC. So, I'm not sure where to go from here. The hard drive has passed diagnostics, so unless it's dying and the tests aren't seeing it (which has happened before), I don't know what to do other than maybe format and reload XP.....