Схлопотал такую ошибку:

DELETE statement conflicted with COLUMN REFERENCE constraint 'FK_forums_Posts_forums_Threads'. The conflict occurred in database 'Forum', table 'forums_Posts', column 'ThreadID'. The statement has been terminated. Object 'forums_Threads' was successfully marked for recompilation. Object 'forums_Posts' was successfully marked for recompilation. Object 'forums_SearchBarrel' was successfully marked for recompilation.

Почему и как с ней бороться - исходники не мои, так что искать там ошибку сложно. Может, что-то в таблице случилось?