every time i turn my computer on and log in a avast window comes up asks to restart my computer is that normal
No, that would not be normal. Try doing a repair of the avast program by following these steps:
My Computer > Control Panel > Add or remove programs > Scroll down to avast! Antivirus and click on it > click on the Change/Remove button > in the next window, scroll down to Repair and click on that to select it > click on the Next button and follow directions given.
I hope this helps you. 
Operating system restart needed by avast message could be solved, in some systems, by deleting the file \setup\reboot.txt
If deleting reboot.txt doesn’t stop the requests for reboot check this:
Check this registry entry (right after computer restart):
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\Session Manager, if it contains “PendingFileRenameOperations”.
Check its contents and if there’s only “reboot.txt” from avast4\setup folder, delete PendingFileRenameOperations, don’t delete any other key.
Backup (export) the registry key before you edit/delete, just in case.
If that still isn’t the problem it could be a tweaking exercise that has an impact on avast.
- Also see 8.3 Tweak issue - Check out this thread and see if some of the possible solutions can help you too.
http://forum.avast.com/index.php?topic=28199.0
ty very much
YW very much!
But does it solve your problem or not?
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