Question : 2008 std server not reporting in to WSUS

I have 40 computers and 3 servers of which 1 is a 2008 std DC.  The 2008 is the only computer not reporting in to WSUS.  What would cause this?'

Answer : 2008 std server not reporting in to WSUS

http://www.mmmug.co.uk/articles/setup-and-testing-of-standby-continuous-replication-in-exchange-2007-sp1