http://msmvps.com/blogs/yoda/archive/2008/06/22/had-to-roll-back.aspxThe ALTER TABLE statement conflicted with the FOREIGN KEY constraint "FK_cs_Referrals_cs_Urls". The conflict occurred in database "msmvps-cs", table "dbo.cs_Urls", column 'UrlID'. Rolled back to CS 2007 as hittingenCommunityServer 2008.5 SP2 (Build: 40407.4157)