Avast detects the most false flags out of any of the popular anti-malware programs. I don't know why people continue to use it when there are many other free ones that are just as good, if not better, that doesn't produce all these false flags.
Believe it or not, Microsoft Security Essentials is quite good. I use that combined with Malwarebytes. MSE has real-time protection. The free Malwarebytes doesn't. So there's no conflict if you use both. They are compatible and both are free.