If you have run your AVG and it deleted the infected files, try going into
control panel/system and click on the system restore tab. Check "Turn off
System Restore" and reboot. It will wipe out all of your saved restore points and create a new one.
I've had this problem where AVG detected a trojen and it kept coming back, or my computer was telling me about it again, after I thought I had taken care of it. Hope this helps