Exchange 2010 RPC issues

During my latest Exchange 2010 transition, a problem related to RPC connectivity arose. Apparently, one of the Client Access servers refused to accept RPC connections on the Address Book Service UUID. This problem occured after the Service Pack 2 installation but wasn't detected until some time after due to the nature of the problem. As some of the clients worked fine, others seemed to work fine and a few had issues with a login prompt appearing sporadically during the day, it was quite a feat to narrow down the problem to a faulty RPC End-point connector on one of the Client Access servers. The quick resolution was to reapply Service Pack 2 but I'm sure there is a way to repair these connectors with some other method. Still, when facing issues after a Service Pack installation, reapply it a few times and things will in all likelihood turn out just great.