We are currently in the process of migrating from Exchange 2010 (SP3) to Exchange 2013 (CU5).
I have approximately 20 pilot users migrated to 2013. Everything appears to be working properly except meeting invites sent by Exchange 2010 users to the Exchange 2013 pilot users are getting stuck in the Poison Message queue.
I've exported the meeting invites and the messages appears to be fine. Additionally I am unable to "resume\retry" those messages. They end up back in the Poison queue.
Does anyone have any suggestion on how I can troubleshoot why the meeting invites are specificially getting stuck in the Poison Message queue.
Thank you!