We have a hybrid deployment between Exchange 2010 sp3 and Office 365. Currently we are just testing hosted email so we only have 25 users on the online side, but these users are unable to use the Room mailboxes on the Exchange side, it just adds the items onto the calendar as tentetive and does not complete the request.
The free/busy status is working both ways and I've tried setting one of the rooms to 'set-CalendaProcessing -ProcessExternal MeetingMessages: $true' with no luck. The room's must stay on the Exchange side, any ideas as to what I should be looking for?
Thanks.