try clearing your browser cache/temp files

TFC - Temp File Cleaner by OldTimer
http://www.geekstogo.com/forum/files/file/187-tfc-temp-file-cleaner-by-oldtimer/
TFC requires a reboot immediately after running. Be sure to save any unsaved work before running TFC.

If no success do this so Essexboy can have a look inside

Follow this guide from our expert malware remover Essexboy
http://forum.avast.com/index.php?topic=53253.0
(post the logs here in this topic and not in the guide)

To avoid using multiple post with copy and paste you have to attach the log`s
Lower left corner: Additional Options > Attach ( OTS log / Malwarebytes log )