Lately Avast has been a little too aggressive. It's not version dependent: I've seen things happen with both version 8 and 9, so it's something within the smaller updates. Anyway, I've noticed that Avast will put some components into quarantine for some highly legitimate long term commercial programs used by specialists, like a Finnish small business bookkeeping program and Steinberg's Cubase 5 which is a professional audio recording program. A viable solution has been to first return the quarantined files by right clicking them and then put the entire folder of the program in question to the exceptions list. Hopefully the people of Avast get this problem fixed soon.
