During my exchange 2010 to exchange 2016 migration I run in to outlook connectivity problem which made it impossible to connect.
There are hundreds of similar issues on google unfortunately none of them solved the problem until I found two solutions on separate blogs and combined them and here is my final fix:
- Set-MapiVirtualDirectory -identity “exchange2016\mapi (Default Web site)” -IISAuthenticationMethods NTLM
- this requires editing Autodiscover and EWS virtual directory using IIS server interface on the exchange 2016 server.
Remove negotiate provider from Windows Authentication.
References:
- this is the first blog thanks to which I was able to get outlook 2016 working unfortunately only with exchange cached mode disable.
- this is the send blog (last post have the solution) which helped me to get outlook 2016 working on the local LAN and behind the firewall as well as with or without using exchange cached mode.
- In addition you need to have MAPI enabled on the exchange 2016 server which is the default but just in case here is the MS link with instructions.