whenI move user from ex2003 to ex2007 ,will happen the error .and the user moved to the ex2007 will not be in service after about 15 miniutes, what can i do ? Event Type:ErrorEvent Source:MSExchangeIS Mailbox StoreEvent Category:Logons Event ID:1022Date:23.08.2007Time:15:21:14User:N/AComputer:SERVERDescription:Logon Failure on database "First Storage Group\Mailbox Database" - Windows account NT AUTHORITY\SYSTEM; mailbox /o=DOMAIN/ou=Exchange Administrative Group (FYDIBOHF23SPDLT)/cn=Recipients/cn=user.Error: 1144 Client Machine: SERVERClient Process: MSExchangeMailboxAssistants.exe Client ProcessId: 0 Client ApplicationId: Client=MSExchangeMailboxAssistants;Action=EventDispatcher

That's just the way it is. Schedule your moves for late at night :-)

Use the move-mailbox cmdlet with the -GlobalCatalog parameter and use the GC in the site of the new Exchange 2007 server. This way, you will be able to access the mailbox almost imidiately after the move. Just make sure the old source Exchange server is available to redirect you. Cheers, Mark