I’ve long recommended AVG for home users. But since the release of version 7.5 there’s been a slow decline in the quality of both the support and the product itself.
Flagging a critical Windows dll file as a virus is a real worry. If that had happened to me, my first thought would have been that I’d stupidly infected myself with something.
The lesson when a result like this comes from the blue is to treat it with suspicion. If one virus checker flags a problem like this, hit it with a couple of others to confirm the problem.