After removing one of our DC with DCPROMO, in the Exchange Server 2003 I got somme errors like : Event Type:ErrorEvent Source:MSExchangeALEvent Category:Service Control Event ID:8213Date:11/15/2009Time:8:57:09 AMUser:N/AComputer:EXCH01Description:Couldn't find an accessible writable domain controller for domain 'DC=domctl01 I realized that DC is still on Recipient Update Service in Exchange System Manager, could I just delete it?

Dont delete the RUS. Map the RUS to a different domain controller and restart the System Attendant service.Raj

Sorry, I forgot to specify the DC which is removed is the only DC for a subdomain only...and in Recipient Update Service in the Exchange the " Recipient Update Service " for that subdomain is still there which point the DC we just removed.The other Recipient Update Service for the main domain is still there and doesn't create any prob. So could I still just delete it?

yes you can. I am sure you dont have any issues on stamping your new users with SMTP address. If no, go ahead and delete it.Raj

Thank you Rajnish for the confirmation!