The following error is ever so common for users of both Exchange and Outlook 2016:
A lot of users are getting this error, and the general conclusion is that Microsoft is to blame.
Microsoft is constantly updating and upgrading its services, and oftentimes doesn’t update the configurations for its users.  This issue usually affects Outlook 2016 but can happen with other versions as well. The message will lead you to believe that you need to update information in your profile, which is impossible to do since Outlook refuses to open and you can’t do anything with it. This occurs because the root domain server is responding to the autodiscover request and as a result, you will not be able to open Outlook, or use your account with it.
What is happening is that Outlook 2016 is hanging when performing the HTTPsAutoDiscoverDomain method. Outlook uses the root domain of your SMTP address to attempt to locate the AutoDiscover service. It tries to connect to the following URL based on your SMTP address in the following xml file: https://<smtp-address-domain>/autodiscover/autodiscover.xml. 
If Outlook is slow finding the autodiscover records, you can tell Outlook to exclude the root domain and other records (SCP lookup, AD domain query, HTTP redirect, and SRV record query) with the following registry entries:
HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\AutoDiscover\ DWORD: ExcludeHttpsRootDomain Value: 1 “ExcludeScpLookup”=dword:00000001 “ExcludeHttpsAutoDiscoverDomain”=dword:00000001 “ExcludeHttpRedirect”=dword:00000001 “ExcludeSrvRecord”=dword:00000001
The reason for individually disabling each of these records is because Outlook’s default settings uses one or more of these methods to reach the AutoDiscover service. If Outlook fails to connect to the predefined URL based on your SMTP address, Outlook tries the HTTP redirect method. If that does not work, Outlook tries to use the SRV record lookup method. If all lookup methods fail, Outlook cannot obtain “Outlook Anywhere” configuration and URL settings. 
This simple solution will help you work around the nasty issue.
Arrows, Kevin. “Fix: Outlook cannot log on. Verify you are connected to the network and are using the proper server and mailbox name.” Appuals.com. N.p., 29 Jan. 2017. Web. 29 May 2017. <https://appuals.com/solved-outlook-cannot-log-verify-connected-network-using-proper-server-mailbox-name/>. 
Bayley, James. “Registry hack to enable Outlook 2016 to connect to Office 365.” Blog.jamesbayley.com. N.p., 01 Dec. 2015. Web. 29 May 2017. <https://blog.jamesbayley.com/2015/12/01/registry-hack-to-enable-outlook-2016-to-connect-to-office-365/>. 
“Posts about ExcludeScpLookup on John Yassa’s Blog.” John Yassa’s Blog – Microsoft till the end. N.p., Web. 29 May 2017. <https://johnyassa.com/tag/excludescplookup/>.