No Internet Connection

I hve Installed the Avast Internet Security 2013 v 8 in My Laptop…Know when i Uninstall it then it Uninstall Completely and reboot…after Reboot when i try to connect to internet then i can’nt…i hve Dial Up Connection…Any Suggestion how i Unistall it Properly…Also when i install the Avast Internet Security Again in my laptop then i connect to internet without problem…i also used the Avast uninstaller utility…any help

http://forum.avast.com/index.php?topic=116901.0