If you are running Exchange 2013 and want to make use of MAPI over HTTP which is the new procotol, you need to ensure that are running Exchange 2013 SP1 or higher.
Your clients will also need to support it, depending on what versions you are running. For information of what is needed you can check the TechNet article below:
First step is to logon to one of your Exchange 2013 CAS servers and head over to IIS. If you expand the “Default Web Site” you will notice a new directory called MAPI.
Now on the same server, launch the Exchange Management Shell (EMS).
If you run the command: Get-MapiVirtualDirectory, you will notice it has an Internal URL set but no External URL set.
Run the following command to enable it:
- Set-MapiVirtualDirectory –Identity “ServerName\mapi (Default Web Site)” -InternalUrl https://mapi.domain.com/mapi –ExternalUrl https://mapi.domain.com/mapi -IISAuthenticationMethods NTLM,Negotiate
Change ServerName with your server name and add in your own domain name where it says (domain.com)
The next step is to do an IISReset.
After this we need to run the final command:
- Set-OrganizationConfig -MapiHttpEnabled $true
If your outlook was still open, you would get the “Administrator has made changes” prompt. Close and open outlook.
Now go and check the connection status for outlook and the protocol should be HTTP.
Hope it helps.