Same here. It's probably just a typo in the latest library, since avast thinks the notepad.exe is the old notepade.exe that the old QQpass trojan used to create.
If you tried to let avast quarantine or delete the notepad.exe file, you'll probably find that you'll cant open the notepad form the exe under \windows\ even with avast shutted down from the task manager.
To solve that issue before the next library update and fix, you'll just need to overwrite that notepad.exe with another, working one, and, of course, leaving avast processes closed in the meanwhile.
