I thought I would pass this on. I use AVG Free. Beginning mid-week I started getting messages about "Invalid Update Control CTF file." It never went away. I do not know what that means, but I did download freeAVG again just now and it seems to have solved the problem. Here's hoping it fixes whatever the problem was.

Congratulations on having solved the problem. There's a good users' forum for AVG Free, where you can ask other users, including experts, for advice. Go to http://freeforum.avg.com/index.php?0