I have the same problem, have been on the phone twice with tech support. The work around I got until they come up with a fix was
1. Delete the temp files from within AVG under Advance settings - Update - Manage - "Delete Temporary update files".
2. Then do an update Now
3. Reboot the PC
So I automated everything to the task scheduler within avg and windows. I set AVG to do an update every 2 hours and set the PC to reboot at 3:00 AM in the morning. I have found this to work for me. As far as the temp files i just have to remember to manually to flush them every day.
From my last post I have found out that I do not have to delete the temp files. All that is required is an update and a reboot, and as previously stated a scheduled reboot by the windows task manager at 3:00 AM works for me.
If you look @ the 'AVG 2013 - Summary' link 'Release Notes' these are the actual changes..
Program update AVG Free 2013.2890 Small Update 3
FIXES & IMPROVEMENTS
AvgSys: Scan will no longer end prematurely.
AvgSys: Fixed detection of Windows Server 2008 R2.
Core: Fixed conflict with registry defragmentation in AVG Tuneup.
Setup: With first/repair installation of AVG, the previously installed MS redistributables will be reconditioned.
AVG Forums Volunteer ModeratorAVG Forum member since - Nov. 27, 2004My total posts on the Old AVG Free Forum - 27,063 AlanHow-To Articles | FAQ | Free Support
I've just spent the best part of an hour in online chat with AVG Support trying to fix this problem. Firstly, they couldn't understand what the problem was. Then they just suggested removing AVG 2013 completely and re-installing. While doing all this, I Google searched the problem and came across this thread on AVG's own forum!! Do their technical guys not communicate known issues with each other. This is worrying.
This problem really needs to be fixed quickly. It is completely unprofessional for me to send out emails which suggest that I'm using out-of-date antivirus definitions.