Outlook 2016 is Slow to Autodiscover Hosted Exchange
Posted by Jay Allred on 16 October 2015 04:34 PM
BizCom Support has found that in some instance Outlook 2016 takes a long time to autodiscover the Hosted Exchange 2010/2013 settings.
This is caused by Outlook trying to obtain a response from the Autodiscover directory on your root domain. If the domain resolves in DNS but does not respond to HTTP queries (i.e. you don't have an actual server to acknowledge them), this will cause timeout errors, and Outlook will try again and again and then finally move on to the next DNS query.
Until Microsoft fixes the issue you have two options:
1. Wait long enough and Outlook will prompt your for your login info and will complete the Autodiscover process.
2. You can add the following key to your registry:
Windows Registry Editor Version 5.00
BizCom Support's recommendation is to simply wait (can be as much as 5-10 minutes) and let Outlook complete the autodiscovery process.
BizCom Support will update this KB article once we know that Microsoft has fixed this issue.