Hi Everyone, I've been trying to setup InterOrg syncronization feature but It's not working very well. I seen error events like those: Event ID:4096 InterOrg: CExchangeController::PerformDAPIWrite action=2 err=c0000121 Warning - DAPI write failed - use DAPI structure to gen good message Event ID:4096 InterOrg: **DAPIWrite** Error: c0000121 (null) (null) (null) master Remote Mailbox Scenario: I have 2 domains(Windows 2000-SP2), Exchange 5.5 SP4, talking by internet mail conector, Mdac 2.7. Description: When a request a new GAL update in InterOrg(Add-in), I can see that the message was sent and received to my domain, but this add-in cannot add anyone name in my GAL. I tried this document in Microsoft web site, but fail (q198798) Thanks in advance