Hiya, I've been tasked with upgrading to Exchange 2010 SP1. I found some issues when I started the process, and was hoping someone could assist as I'm a bit out of my depth. The DCDIAG Output is below: http://pastebin.com/Mk8sNWV2 The RepAdmin /Showreps Output is below http://pastebin.com/XpBBrEcV I noticed that it is trying to replicate to STCOL-DC-P03, which doesn't seem to exist anymore. The engineer before us had it setup more like an 'enterprise' than a small business, for a 5-10 person company. I assume I need to stop it from trying to replicate. Backups are up to date. AV and everything is A OK. Any help would be great. Thanks, Simon DCDIAG_OUTPUT.txt