For the last few months avast has been blocking groupworld.net as url:mal. Seems to be a false positive due to us using a plugin. Reporting as a false positive, and also contacting avast (through both website contact form and twitter) doesn't seem to help.
I think the issue is in our plugin (which is classed as 'very poor rating' in the 'browser cleanup'). There doesn't seem to be any way for users to rate add-ons, so I assume avast itself has automatically given us the 1-star rating. My guess is that it's because the plugin is for web conferencing, and we have a 'remote control' option in the desktop sharing which listens to the keyboard. I assume that this means that avast automatically classes us as potential spyware.