MAPI over HTTP was introduced in Exchange 2013 SP1. It is now default protocol and enabled by default in Exchange 2016. You can configure URL for MAPI over HTTP using Exchange Management Shell (EMS) only. Open EMS and type following cmdlet to set external and internal URL for MAPI virtual directory.

Set-MapiVirtualDirectory -Identity "MBG-EX01\mapi (Default Web Site)" -InternalUrl https://mail.domain.com/mapi -ExternalUrl https://mail.domain.com/mapi -IISAuthenticationMethods Negotiate

To verify MAPI URLs type following cmdlet in EMS as shown below,

Get-MapiVirtualDirectory -Identity "MBG-EX01\mapi (Default Web Site)" | fl server, internalurl, externalurl