I do ban a user and then delete all his posts and replies, and then delete the user with 6.0.3 without any problems
if you delete the user first it will be tricky to delete the posts from that user... maybe then the board goes crazy but it should not..
Could it be that that user had starte all the threads in the forum? perhaps it was the only forum in the catefgory and now the forum does not show...
