All the shields of Avast are disabled. The GUI module reports,
"The avast! antivirus is off: Start"

I can not manually enable Avast and when I try to do that, I get an error code:
0x80046401
Avast also reports that C:\Windows\System32\mmc.exe is shutting down the real time shields of Avast. However, a VirusTotal scan of the file doesn't say it is infected (0/47 scanners). The process that avast reports is trying to shut it down keeps changing as you see here:

Moreover, the Service Manager says that the avast service, AvastSvc.exe has been started.
The GUI module of Avast reports that I haven't yet registered Avast but when I check Maintenance -> Registration, the expiry date is shown to be 7/2/2014.

I also can not generate support packages (zip files with program logs, minidumps, other technical info). When I do, I get another error code: 0x3e3
Please let me know how I could fix this problem.