Symptom

Office 365 Exchange Online users cannot book conference rooms that resides in Exchange Server 2003 server on-premise in Hybrid deployment.

 

Cause

The issue occurs because Auto Accept Agent is not installed.

 

Resolution

To work around the issue, move the resource mailbox to Exchange Server 2010 mailbox server.

 

Note: The Auto Accept Agent is configured by default in Exchange Server 2010.

 

More Information

Understanding Auto Accept Agent

http://technet.microsoft.com/en-us/library/bb124617(v=exchg.65).aspx

 

Exchange 2003 Auto Accept Agent vs. direct booking

http://blogs.technet.com/b/exchange/archive/2006/02/22/420275.aspx

 

 

Applies To

Office 365 Exchange Online