When you have trouble Set Up Outlook Using AutoDiscover you have to Manually Setup Outlook.

 

Here the Proper Step to Follow:

 

First, log into the Office365 portal, then hit on Outlook and wait for the Outlook Web App to load. Then press the help circle on the far right and select the ‘About’ option as here:

Now you’ll see the ‘About’ section which has a whole mess of detail few people really want to see. Your concerned with the ‘hostname’ bit of the setup, and that’s because you need to know what server your Office365 installation (in the cloud) is running on.

Once you have your hostname, you need to make a minor adjustment – adding the word ‘mailbox’ to the equation. So if like above you’re sitting on ‘amsprd0302.outlook.com‘, your Exchange server address is really ‘amsprd0302.mailbox.outlook.com‘. Now, you have pretty much all the detail you need. (Please note: Don’t use these settings as you may not be on this server and any attempt to authenticate will fail.)

Now you need to launch Outlook (2007 SP2 or later) and setup the new profile and account. The devilishly charming IT guy in his wisdom and ridiculous self confidence has of course deleted all the other profiles from the Mail control panel option and of course backed up his NK2 files before doing so – that’s what makes him that little bit special!

So in the Exchange Account Setup for Outlook, your server becomes the one with ‘mailbox’ in it. The username is self explanatory, and it entered in the format of ‘user@domain.com’. Don’t go anywhere just yet though, because you need to head into the ‘More Settings’ options, where you’ll find the secret sauce to this Outlook Anywhere business you so well touted to your business clients when you sold them on the whole ‘cloud’ thing. Head for ‘Connection’ and mark the option box for ‘Connect to Microsoft Exchange using HTTP’ and then select the ‘Exchange Proxy Settings’ box. Now you’ll enter the Exchange server name without the ‘mailbox’ addition and check all the boxes, add in the term ‘msstd:outlook.com’ into the principal name section and change authentication to basic. Now press OK twice, then you can do the ‘Check Name’ thing to see if you hit the jackpot. Of course, you will be prompted for credentials, but hopefully the sign-in tool for Office365 you installed earlier (remember the thing that told you there were ‘manual steps’ to complete – yeah, that!) will keep suppressing future authentication challenges and Outlook will work “just like it normally does” – yeah, the devilishly charming IT guy did promise his customer that assurance, the cocky SOB that he is, and it looks like he’s gonna get away with it too!

 

Hope this Help.