I currently have multiple Exchange 2003 servers in 1 domain. I am currently decommissionin SERVERA and have installed SERVERB. I have moved all mailboxes from SERVERA to SERVERB. Upon uninstalling Exchange on SERVERA it states that RUS is still on the box. WHen i attempt to move RUS from A to B it gives me the following error "Before creating a recipient update service, a member of the domain admins security group inthe chosen domain must run exchanger server setup with the /domainprep command. ID NO. c1034a31. What would be the cause of this error? and would running /domainprep a second time pose a potential problem.