> These are 2 sites within the same organization. In fact, So when you installed Exch5.5 on the Win2k server you used the service account from the other domain and attached it as a new site at that time? In other words, you had network connectivity and the installation appeared to work fine but now the sites aren't showing up properly in the Exchange Admin program? If that's the case then I assume that you've already verified that you can map network drives in both directions and connectivity is not the issue. What are you getting in the event logs on the two boxes? I'd probably try deleting and recreating the connectors if you haven't already. I've also successfully used site connectors on 64k frame connections....it isn't recommended but that doesn't mean it won't work.