This blog post discusses several top issues seen to date by the Microsoft Exchange Product Support Team regarding the Standby Continuous Replication (SCR) feature introduced in Exchange 2007 Service Pack 1. We wanted to share this information as it can be used as a preventative measure as well as for resolving issues you may have experienced. It is understood that this will not cover all that can possibly go wrong, but it should give you some good pointers in some situations that you might have seen.

Read more at source: http://msexchangeteam.com/archive/2008/05/28/448929.aspx