SIM 5.3 only reports ip address in the system name column

[Derek_56]

Look (or have your DNS admins look) at all the records for the zone your target system (the one you are adding, not SIM) and make sure you don't have duplicate records for the same IP address. The only time I've seen this is because there are multiple entries in DNS or because you don't wait long enough between your deletion and readdition of the server into SIM. If DNS is good, then delete the record in SIM and wait 15 minutes before you do a re-add. If you still have problems, try looking at your system and application (\logs\mx.log) to make sure you're not having some other failures occurring on the SIM server.