AIS has been working fine the last couple of days. For the last few hours, however, it doesn’t want to update.
I had a message that my defs were out of date (so, obviously the auto-update had failed), and when I tried to do a manual update the process refused to complete. On, I think, the 3rd or fourth attempt it “looked” like it completed, but the program is giving me different indications in different parts of the UI.
The screenshot shows what I mean.
Thanks 
Can you try to repair your installation?
Go to Control Panel > Add/Remove programs > avast! antivirus > Remove. Then choose Repair function in the popup window (Repair).
If this does not help, can you uninstall / boot / install / boot again?
Thanks, Tech.
Before you replied, I tried to repair the installation with no effect.
The uninstall/reinstall seems to have cured it, however.
We’ll wait and see how the program acts over the next few days. Unfortunately, AIS has proved to be less stable then I normally find acceptable in a program (especially security related). But, I’m willing to wait a few weeks to see how it goes.
Thanks for the assist!
Before going through the extreme of an uninstall/install, try a simple reboot next time (if it happens). If that fails, then try the repair. Some times there is a glitch in the system and it fixes itself on the next update as well, but a reboot usually does the trick. 
Always the first thing I try…an old habit from the early days of Windows that I’ll never lose