Hello Patrick,
You can rename the AVG program folder from the command prompt. Then boot normally and run the repair installation of AVG.
See for example an excellent description here http://forums.avg.com/ww-en/avg-free-forum?sec=thread&act=show&id=132969#post_132969 by Pulse21
Thanks,
Jan
Hi
I am trying to remain calm but it's getting harder and harder. I have lost my main PC since Friday AM due to the bad AVG update like thousands of others.
I have been all day on the AVG forum and now they seem to be down, I don't know why, I tried to access them on 2 other non infected PC's to no avail.
Ok enough of the rant I was wondering if someone would have a final idea before I put my Windows 7 DVD in there and restore to factory new and lose my stuff (I back up but still stuff gets lost).
I have done the following:
-Create an AVG USB boot disk which failed (I went into my bios and boot order and I don't see a USB boot option only DVD and HD.My PC is 1 year old AMD Phenom II, I am surprised I don't have that option.
-So I tried to create an AVG bootable DVD with their .ISO file which I got done, I checked the file was burned on it and it is there.I made sure to change the boot order in my PC and put the DVD first. That failed, I tried 4 times.
-I have rebooted my infected PC probably 50 times in the last 2 days and have hit various F keys to no avail.F8, F3, F12,F11 and the ESC key to no avail.
-I can't enter safe mode, tried countless times, it brings me to the startup repair utility.
-Startup repair will not work, it fails to restore to an earlier date.
-The only 2 things that I know I haven't done yet are:
1)Use my windows 7 DVD to do a fresh install of windows (My last resort if this post fails to help me.)
2)Do anything from the command prompt which I can access. Guys is there anything I can type at the command prompt to help me?
I appreciate the help.
Thanks
Patrick ;-(
(Logging off now and going to try to relax in front of the TV with a scotch on ice.)

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic