Replace all your vb files with a fresh set from the vb package (your version). This will take care of cleaning up all your forum files. Then scan all the other files in your server space and look if they have been injected with malicous codes and clean them up if they have been. Look also for anything out of the ordinary, like files that shouldn''t be there etc. Then scan your pc for any malware programs and change all your passwords (for your forum, ftp, cp of your host etc). And upgrade your forum to the latest version if you are running an older version. And as last but not least, inform your host so they can check their access logs and see how the hacker got in. Hope it helps.