I noticed the discussion regarding "avg anti virus doesn't like downloads" and wonder if the AVG notification I am shown when it attempts to update is caused by CCleaner deleting some aspect of the AVG "update control CTF file." I am using AVG v8.0.175 on WinVista v6.0.6001 w/Service Pack 1Build 6001
I have encountered this problem several times now. After the first time I was unable to use AVG's automatic update, I went to their website and manually downloaded the latest virus definitions file. Upon restarting my computer the next time after that session I again encountered the "Invalid update control CTF file" problem when automatic update ran. Their website offers no information regarding the CTF file which prevented me from rectifying the situation I encountered. I then re-downloaded the full AVG software installation, uninstalled the version I couldn't update, and successfully installed the latest version of the software. After installation I updated the program to be sure I had the latest virus definitions update.
I had no problem with the AVG automatic updates for a few days of computer operation. Yesterday, I ran CCleaner and upon restarting the computer today I again encountered the "Invalid update control CTF file" problem. I searched the AVG website again for a solution to the situation and luckily found "1567: AVG update issue - Invalid update control CTF file" which provides a helper application that addresses this issue by deleting the corrupted CTF file. After running that app I was able to successfully utilize the automatic update function and install the latest virus definitions.
I surmise that CCleaner causes the corruption, and if it is in fact what causes it, I would like to avoid this hassle in the future. Any insight or suggestions regarding this issue?