I had a problem with AVG Free forcing my computer to restart several times a day. It first forced a restart after an update and I didn't pay too much attention, just did the restart. Then the next day I came in and my PC was halted and AVG was requiring a restart. Again, I did it with out worrying about it too much.
The problem got worse over time to where today I had had enough. I came in and it wanted to be restarted. I restarted it and then it immediately wanted restarted again. I restarted the second time and .... you guessed it, it wanted restarted again.
Normally by now, if this were my computer that software would have been replaced with Norton a long time ago. Unfortunately the company requires THAT software. I also have to have my PC running 24/7 so that others can access shared files during the night as needed.
So I went off to the message boards and found that I am not the only one having this problem! Seems it is happening to a lot of people. I had to look for a while before finding a resolution. Most of the people having problems have not yet found a solution so I decided to post this here.
After a lot of digging I found where someone had figured out the problem was a failed update and there is a file left behind. "Program Files\Grisoft\AVG Free\wait4sd". Delete this file and then force an update of your AVG. The problem should resolve itself.
This resolution is approved by Grisoft (note that this was impossible to find until I knew the name of the file and then googled the file name then found the link to Grisoft in a different message board.
So, hope this helps some other poor soul stuck with this problem....