Hi - I installed Avast 4.8 yesterday on a new Windows Ultimate SP1 x64 machine. By “new”, I mean a machine that was built 2/5/2009 and has been operating off-the-net (except for Windows Updates) for a month. All seemed fine until this morning.
This morning, at bootup, the machine freezes after a few minutes at “Configuring Updates … 0 of 7”. Again, I just installed Avast 4.8 Home Ed. yesterday, and it booted fine yesterday a couple of times and I recall hearing the “database updates have been installed” voice/sound TWICE last evening. Odd … why twice in one 6 hour period?
The machine was shutdown over night and powered up this morning, tried to, that is … that’s when the freezing started. 
I don’t know which Microsoft updates are attempting to be installed, but the machine was current with all updates as of Monday, 3/9/2009. I’m not even sure that the problem is directly related to Avast, but I was curious if anyone else is having this problem.
Is anybody else seeing this?