The day Avast went wrong, yes perhaps false positive. As I just turned on the PC, it reported the following files to be infected:

Vistastartmenu.exe of Vista Start Menu
Spywareterminator.exe of Spyware Terminator
Skype (even Skype!)

At first, I didn’t think it was false positive, I got the warning against Vista Start Menu, I don’t know much about the publishers of the software, but then next was Spyware Terminator? Harder to believe, by checking online, I saw many others were complaining about this issue. The only thing you can do, is click no action or the x button, until Avast get fixed.

In my case, it didn’t work with Vista start menu, it kept showing the warning. So, I ctrl+alt+del , went to processes and chose to end the task for vistastartmenu.exe. Only then I was able to close avast warning.