Greetings and salutations. I am having an odd problem here. I have set up a federation trust between my on-premise Exchange 2010 SP3 CAS and the Microsoft Federation Gateway. After that I set up an organization relationship between the two organizations. I have followed the procedures in this article: https://technet.microsoft.com/en-us/library/ff601760(v=exchg.141).aspx

Free/busy lookups only works from on-premise to office365. Meaning, on-premise users can see the free/busy information of office365 users. But office365 users cannot see free/busy information of the on-premises users.

In Outlook, set up with an office365 user, the errormessage displayedv when hovering the free/busy No Information field is: No free/busy information could be retrieved and The recipient's server could not be contacted.

Running the test-organizationrelationship from both on-premises and office365 shows no errors. It seems it is all set up correctly.

Does anyone know if there are any logs I can have a look in to see what is going on?