If you really want help, you will need to provide more details.
Keep in mind that we can't see what is going on on your system.
What os/service pack?
What exact version of avast?
Any other security software installed?
If not, did you had other software installed and if so which one(s) and how did you delete them?
Have you tried disabling the shields one at a time to see if a particular one is causing the problem?
