We have strange problem with Teams “Calendar” app (ex. Meeting app), which is not showing in Teams client application, when user’s mailbox is on premise. According to Microsoft, we have to be running Exchange 2016 CU3 + to be supported. Our environment is Exchange 2016 Ent. CU13 + S4B Ent 2015 CU9 and coexistence mode “Skype for Business with Teams Collaboration and Meetings”.
Everything else is working perfect with the integration. This is happening with all users. I have done different tests (Autodiscover, EWS..) from “Microsoft Remote Connectivity Analyzer” and everything is “green”. If user’s mailbox is migrated to Exchange Online, the user is able to see the “Meeting app”.