To fix this issue, you also need to add a registry key. If you change the protocol between the MAPI over HTTP and RPC, the primary mailbox isn't displayed.A number of MAPI over HTTP issues are resolved, including problems with Outlook crashing, email attachments are corrupted during the download, public folders won't open and display the following error message: e Cannot display the folder.
These errors occur because Outlook 2016 for Windows doesn't support connections to Exchange Server 2007 and earlier.
For instructions on setting up a DNS record, see Set up DNS records for Cloud Office email and Skype for Business.
Exchange 2016 offers public folders on a hosted environment and has the following limitations: The spam handling in Exchange 2016 is the same as Exchange 2013, and is different from Exchange 20.
Although we do not anticipate any issues with the migration, we recommend that you back up your data before the migration.
You can back up your data by performing a PST export with Outlook. Ensure that your Autodiscover DNS record points to Rackspace.
This fix requires either Exchange Server 2013 CU12 (KB3108023) or Exchange Server 2016 CU1 (KB3134844) installed on the Exchange backend as well.