I use AVG 8.0 Free with Vista. AVG 8.0 normally checks and updates its virus definition automatically, but since the past couple of days it was not updating automatically. When I try to manually check for updates, I received this error message “Invalid Update Control CTF File”.
After doing some research, I found the solution to this problem on AVG forum. You need to remove the CTF temp files in C:\Documents and Settings\All Users\Application Data\Avg8\update\download. There were two files in that folder - avginfoavi.ctf and avginfowin.ctf, deleting them solved the problem and I was able to update AVG 8.0 with latest virus definitions.

wrote, on November 15th, 2008
Thanks. It works. thanks for solving the problem.
wrote, on November 15th, 2008
Is this problem unique to Vista? I run XP and AVG, haven’t noticed any issues recently.
wrote, on November 16th, 2008
[...] [Via] [...]
wrote, on November 17th, 2008
As you know, I never did switch to Vista!
wrote, on November 17th, 2008
I now use ClamWin on my laptop, it’s just as effective as AVG, but uses less memory. Check it out and try it out. I’m still on Windows XP though, I doubt I’ll make the move to Vista. Just waiting for Windows 7 for a potential upgrade, but other than that, I’m still very happy with my XP.
wrote, on November 19th, 2008
thanks for the tip, it work beautifully now… cheers
wrote, on November 21st, 2008
1. It does happen of XP.
2. It does work on XP.
Thank you
wrote, on November 23rd, 2008
No it is not unique to Vista.
My problem is that I have manually removed the CTF files. I have also downloaded a lil program (from an AVG Beta tester) that removes the CTF files.
Neither of these have worked for me. Is there any other solution to this issue?
I would really like to update my AVG
wrote, on November 23rd, 2008
I found the fix…
There are 2 files that can be deleted as AVG will recreate them. If they become corrupted you will have to remove them manually.
In Windows XP, go to:
C:\Documents and Settings\All Users\Application Data\Avg8\update\download
and delete
avginfoavi.ctf and avginfowin.ctf
In Windows Vista, go to:
C:\ProgramData\avg8\update\download
and delete these 2 same files.
Re-run the update.
Fixed.
wrote, on November 24th, 2008
I’ running XP and have this problem but the fix didn’t work for me. Any other suggestions?
wrote, on November 30th, 2008
thanks for solving problem.
wrote, on December 13th, 2008
It does happen on XP to - I have XP SP2 and AVG8 worked fine for about month then it started puking this error. Removing the CTF files did not help at all. Removed and reinstalled it… Still does not solves the error - it must be somewhere in the registry.
wrote, on December 15th, 2008
@Jon from November 23, 2008:
Per your first post, “My problem is that I have manually removed the CTF files” which you state did not work. Next post you indicate “I’ve found the fix” which is deleting (removing) the same CTF files you stated you’d already removed. The “fix” you discovered was the point of the page you commented on. It’s terribly impolite of me to disrespect a fellow human I’ve not met - however noise like you put down w/ your two posts restating info already present is proof some shouldn’t be allowed to crawl to the keyboard. Same for me, throwing this here perhaps, eh…not contributing to the subject at hand. However maybe it’ll help you reconsider next time you share your wondrous insights w/ a world more intelligent than you. Cheers!
wrote, on December 16th, 2008
im getting error :- Invalid update control CTF file
my AVG version is 8.0.176
im using windows-xp sp2
pls help me out,
wrote, on December 21st, 2008
Yup It’s works too for me.
I’m using AVG 8 OS Vista Ultimate 64-bit on my laptop.
Thanx!
wrote, on December 21st, 2008
Cheers mate. Worked perfectly. Thanks.