I have one root domain controller and one exchange server . i introduce new child domain controller . i want the child controller users get mailbox through that exchange server. i install domainprep in child domain controller. I give the delegation full exchange administrator privilege on child domain administrator . after that i configure recipient update service , i join domain give proper exchange server when i click finish i get some error is shown below. The specified group type is invalid Facility:win 32 ID no: c0072141 Exchange system manager

Hello, Did you create new Domain RUS for child domain and add domainpre there?Arun Kumar | MCSE - 2K3 + Messaging | ITIL-F V3

Detail information you can refer to the article below: Creating Exchange Recipient Update Service instances for remote domains/child domain http://support.microsoft.com/kb/275294/en-us Regards, Xiu