Sadly for you DivakarBal I'm glad to have someone else chime in - presumably with a different ISP hosting your exchange account.
Rackspace has acknowledged that it does not yet have MAPI over HTTP enabled, but that reg tweak to turn off this "protocol" did not solve my problem..
Perhaps our friends at MS will decide to back out of removal of RPC over HTTP, or otherwise determine why autodiscover doesn't work for us :)
The best bet is opening a support case so the engineers can look at your system.
Did Rackspace say when they were going to implement mapi over http?
This is the key you set?
Key: HKEY_CURRENT_USER\Software\Microsoft\Exchange
DWORD: MapiHttpDisabled
Value: 1
Did you also do this (from http://blogs.technet.com/b/exchange/archive/2014/05/09/outlook-connectivity-with-mapi-over-http.aspx)
I updated the registry key to disable MAPI/HTTP on a client but the connection didn’t change?
The registry entry simply controls what Outlook sends to Exchange about its MAPI/HTTP capability during an Autodiscover request. It does not immediately change the connection method Outlook is using nor will it change it with a simple restart of Outlook.
Remember, the Autodiscover response Outlook gets only has MAPI/HTTP or RPC/HTTP settings in it so it has no way to immediately switch types. You must allow Outlook to perform its next Autodiscover request and get a response from Exchange after setting this
registry entry before the change will take place. If you must attempt to speed along this process, there are two options.
- Set the registry entry as you wish, close Outlook, delete the Outlook profile, and then restart Outlook and go through the profile wizard. This should result in an immediate switch, but any settings stored in the Outlook profile are lost.
- Set the registry entry as you wish, close Outlook, delete the
hidden Autodiscover response XML files in %LOCALAPPDATA%\Microsoft\Outlook, and restart Outlook.
- Restart Outlook once more to complete the switch.