Not sure if it was suggested and tried, but AVG provides removal tools here
- just be sure to download the correct bitwise (32 / 64) & product (2012 /2013). There seem to be other removers available - I don't know any more about them though.
gregrocker said:
You can Search the Registry to Delete all AVG keys. Set a System Restore Point - Create

Then type regedit in Start Search box, rightclick result to Run as Admin.

From Edit tab, click Find, type AVG to Find Next. Delete any AVG keys or sub-keys. Be careful: AVGeneral in Adobe Reader is not an AVG key! Don't delete unless you're sure it's AVG-related. You can google it since others have probably already struggled with this bloatware mess.

Keep clicking Find Next until it stops finding them.