Might want to recheck your ubb control panel settings.
Control Panel Â» Primary Settings-Advanced
Look for referrer check there are two settings.
Then double check:
Control Panel Â» DB, Paths & URLs
Also a url to your site would be helpful as well as what version ubb you are using.
Last edited by Ruben; 11/09/2011 5:05 PM. Reason: Added comment