I believe that I had the issue where after an update to the Avast database, Windows 7's security center still showed Avast as "out of date". (I had restored an older ghost image, Avast updated its database, and the red flag remained.) I believe a reboot resets the security center to reflect the correct status, which is why it's typically not seen.
To be honest, it didn't mean much to me at the time till I saw it mentioned in another thread in this forum, and then I realized what had happened.
Everything else seems to work.