In your HJT log I noticed that you have Big Fix.From past experience,this is a program that was situated with Norton AV and Symantics programming.When I had problems with a buddies system,I found that it conflicted with AVG.Not sure is this would or has happened to you,but it might be something worth consideration.I'm sure that Judy or PP will either add to this or dismiss it,but I thought it worth mentioning.