Autodiscover Registry To stop Autodiscover Connection Issues
Autodiscover Registry Edit to Disable Office 365 Autodiscover and stop Autodiscover Connection Issues
Navigate to Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\AutoDiscover
Create a new DWORD (32-bit) Value
Value data = 1
Name = ExcludeExplicitO365Endpoint
Autodiscover breaks both existing profiles, and newly created profiles - fortunately this reg fix will stop autodiscover pointing to the wrong url so you can use 3rd party exchange servers.