It is possible to disable certain autodiscover steps by creating DWORD entries in the HKEY_CURRENT_USER\Software\Microsoft\Office\<version>\Outlook\AutoDiscover registry key.

Note. <version> can be 16.0 for Outlook 2016, 15.0 for Outlook 2013 and 14.0 for Outlook 2010.

The following DWORD entries can be created:

• ExcludeHttpRedirect
• ExcludeHttpsAutoDiscoverDomain
• ExcludeHttpsRootDomain
• ExcludeScpLookup
• ExcludeSrvRecord
• ExcludeLastKnownGoodURL (Outlook 2010 version 14.0.7140.5001 and later)
• ExcludeExplicitO365Endpoint (Outlook 2016 version 16.0.6741.2017 and later)

Add the DWord of 1 to any of the above to skip the check

Per here https://support.microsoft.com/nl-nl/help/2212902/unexpected-autodiscover-behavior-when-you-have-registry-settings-under