Article ID: 2838688 - View products that this article applies to.
You set up an organization relationship to share information between two organizations. This might be in either a hybrid deployment of Microsoft Exchange Online in Office 365 and your on-premises Microsoft Exchange Server environment or two on-premises Exchange Server organizations.
However, you experience issues when you try to use the organization relationship. For example, free/busy lookups don't work. When a user tries to look up free/busy information about another user, the user receives an error message that resembles the following:
Other features that require the organization relationship and that rely on the Exchange Web Services (EWS) may also be affected. These features include MailTips and delivery reports.
Free/busy information couldn’t be retrieved because the attendee's Mailbox server is busy
This issue occurs if the following conditions are true:
Office 365 uses Exchange Server 2013. If you're running Exchange Server 2010 in the on-premises environment, the versions of Exchange in Office 365 and in your on-premises environment are different. This combination, together with the misconfiguration of having the TargetSharingEPR parameter set, causes this issue.
To resolve this issue, connect to the organization by using Windows PowerShell, and then set the TargetSharingEPR parameter to Null. This should be performed for all organization relationships.
To set the TargetSharingEPR parameter to Null, follow these steps:
It's very important to make sure that Exchange Autodiscover is set up correctly for all organizations that use an organization relationship. If Autodiscover isn't working correctly, there's no supported way for you to use organization relationships.
Still need help? Go to the Office 365 Community
Article ID: 2838688 - Last Review: July 9, 2014 - Revision: 7.0