Hello All... After Greetings... I am facing problem with following setup... Root Domain is with 2 DC's both are GC's also...Exchange 2000 SP3 running on top of one GC. I have several child domains and all are domain-preped and RUS is generating E-mail address. For one of the Child Domain. One administrator accidentally deleted the RUS ...when I am trying to add RU for that domain..i am getting a error meassage stating domain should me domain prepped with /domainprep switch which I did..but I am not able to add the RUS. Apart from this error I am getting warnings in Directory service event logs with Event ID 1265. which points to DNS issue...where as DNS name resolution is working properly. I even restarted my DC/GC/exchange server..child domain DC but problem remains same...so any ideas..any clues.. Thanks in Advance, Regards, Vijay Dogra.