I'm having the same problem with build 1001 and Vista.
Program details:
avast! Antivirus
C:\Program Files\Awill Software\Avast4\setup\setup.ovr
And when i click "Show the message" i get a dialogbox which has avast Antivirus as title and with the question:
Do you want to restart Windows now? And two options, yes or no.
I'm gonna try to change avast4.ini and see if it helps.
*Update*
Then when I run a manual iAVS update, it says my DB is updated (which is correct), but then Avast wants me to restart... why? I got the latest 1001 build, but anyway I'm guessing the popup problem happens only for people who has a Avast, which needs a restart.
Gonna restart next time, can't now