It started happening yesterday, and I thought it's going to go away. I've also noticed a lot of other people started complaining about this... now it hit my PC too.
Tried everything, not a single thing helps.
This is exactly what I've tried so far:
1.) Checked contents of the C:\Program Files\Alwil Software\Avast4\Setup\setup.log file. Shows me absolutely nothing.
2.) Deleting the file C:\Program Files\Alwil Software\Avast4\Setup\reboot.txt
Of course, nothing helped. So I tried tweaking the registry right after computer restart.
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager, "PendingFileRenameOpertaions" item.
It contained "reboot.txt" only, so I deleted PendingFileRenameOperations item, not anything else.
Nothing helped...
So as much as I've hated to do that, I've decided to completely remove avast! from my computer using avast! Clean utility called aswclear.exe
Removed every single trace of avast! in registry. Restarted my system, installed the latest avast! version from the web site, even did a brand new registration and got my avast! Home edition serial number (the old one was expiring soon anyway). After all configuring, system restarted...
Guess what... same thing is happening again. avast! keeps asking me to reboot my computer even it hasn't updated anything, not a program update, not a virus definitions update. I am stunned as what is happening here and have no solution for this at this moment.