AVG says CommonRes.dll signed with broken signature

I am running the latest Avast 7.0 on Windows 7 64 bit. I did a clean uninstall of 6/install of 7, everything is running well.

Then I ran AVG’s offline (separate Linux boot CD) virus scan, as an additional way to check my system. I let the AVG CD update its engine and database before scanning my boot hard drive (partition C:).

My PC came up clean, except AVG gave me a notice that “CommonRes.dll:/CommonRes.dll The file is signed by a broken digital signature, issued by: Google Inc.” (The notice had the full partition and Avast directory path in it - I forgot to write the entire thing down, but it was correct.)

When I booted back into Windows and checked the digital signature on that file, Windows said the Avast digital signature was okay, and that it was signed by Verisign (and the Verisign signature was okay, too).

I did not get a result like this on any of the other Avast dll’s (all of which are also signed) - just this one.

I assume AVG’s scanner made a mistake, but what an odd mistake. Any thoughts from the Avast crew?

AVG doesn’t report on the file itself, but rather on something it extracted from inside of that file.
You don’t have to worry about that - the file itself is OK (as you confirmed by checking the signature in Windows).