I am having a problem installing Exchange 2007 SP1 that I am not able to solve myself.Wanted to try some forums before contacting Microsoft, maybe someone have seen thisand knows about a fix.I have run PrepareSchema with success.I ran PrepareAD with success but only after moving Schema Master and Domain NamingMaster to the root domain.But when I try to run PrepareDomain on the two domains with users I want to enable forExchange use I get an error about an object that does not exist.Cut from ExchangeSetup.log:[08.02.2008 14:10:42] [2] [ERROR] Active Directory operation failed on zevs.w.XXX.YY. This error is not retriable. Additional information: The specified user does not exist.Active directory response: 00000525: NameErr: DSID-031A0F80, problem 2001 (NO_OBJECT), data 0, best match of: ''[08.02.2008 14:10:42] [2] [ERROR] The object does not exist.[08.02.2008 14:10:42] [2] Ending processing.[08.02.2008 14:10:42] [1] The following 1 error(s) occurred during task execution:[08.02.2008 14:10:42] [1] 0. ErrorRecord: Active Directory operation failed on zevs.w.XXX.YY. This error is not retriable. Additional information: The specified user does not exist.Active directory response: 00000525: NameErr: DSID-031A0F80, problem 2001 (NO_OBJECT), data 0, best match of: ''[08.02.2008 14:10:42] [1] 0. ErrorRecord: Microsoft.Exchange.Data.Directory.ADOperationException: Active Directory operation failed on zevs.w.XXX.YY. This error is not retriable. Additional information: The specified user does not exist.Active directory response: 00000525: NameErr: DSID-031A0F80, problem 2001 (NO_OBJECT), data 0, best match of: '' ---> System.DirectoryServices.Protocols.DirectoryOperationException: The object does not exist. at System.DirectoryServices.Protocols.LdapConnection.ConstructResponse(Int32 messageId, LdapOperation operation, ResultAll resultType, TimeSpan requestTimeOut, Boolean exceptionOnTimeOut) at System.DirectoryServices.Protocols.LdapConnection.SendRequest(DirectoryRequest request, TimeSpan requestTimeout) at Microsoft.Exchange.Data.Directory.PooledLdapConnection.SendRequest(DirectoryRequest request, LdapOperation ldapOperation) at Microsoft.Exchange.Data.Directory.ADSession.ExecuteModificationRequest(ADRawEntry entry, DirectoryRequest request, ADObjectId originalId) --- End of inner exception stack trace --- at Microsoft.Exchange.Data.Directory.ADSession.AnalyzeDirectoryError(PooledLdapConnection connection, DirectoryRequest request, DirectoryException de, Int32 totalRetries, Int32 retriesOnServer) at Microsoft.Exchange.Data.Directory.ADSession.ExecuteModificationRequest(ADRawEntry entry, DirectoryRequest request, ADObjectId originalId) at Microsoft.Exchange.Data.Directory.ADSession.Save(ADObject instanceToSave, IEnumerable`1 properties) at Microsoft.Exchange.Data.Directory.Recipient.ADRecipientSession.Save(ADRecipient instanceToSave) at Microsoft.Exchange.Management.Tasks.SetupTaskBase.Save(ADRecipient o, ADRecipientSession recipientSession) at Microsoft.Exchange.Management.Tasks.InitializeDomainPermissions.InternalProcessRecord() at Microsoft.Exchange.Configuration.Tasks.Task.ProcessRecord()[08.02.2008 14:10:42] [1] [ERROR] Active Directory operation failed on zevs.w.XXX.YY. This error is not retriable. Additional information: The specified user does not exist.Active directory response: 00000525: NameErr: DSID-031A0F80, problem 2001 (NO_OBJECT), data 0, best match of: ''[08.02.2008 14:10:42] [1] [ERROR] The object does not exist.Someone seen this? Someone know how to fix this?Thanks,- Roger

FYI:The not too obvious solution was to configure one DC in the root domain to be a Global Catalog server.The setup had one root domain and three subdomains, with two GC's total, both in a subdomain.- Roger