I have added exchange 2000 server (from my windows 2000 domain) into my exchange 5.5 site on my NT4 domain. I have config, two way recipient and two way public folder CA's that all replicate fine between a set of OU's in my win2k domain and the containers in exchange 5.5. I have added a second administrative group in ESM (this appears as a new site in Exchange 5.5 admin). I added a new exchange 2000 server in this admin group and created new mailboxes on this server. These users exist in a different OU in my win2k domain I have created a one way recipient CA from this new OU to exchange 5.5 but the users don't appear and I get no errors when I force replication? Any ideas? Regards Leo