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I've run autodiscover tests via testconnectivity.microsoft. When i delete the users mail profile, and reconfigure, outlook 2016 successfully connects, but when outlook 2016 is closed and re-opened, same issue.
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So Outlook 2016 goes in disconnected mode. I am able to successfully build users outlook profile in outlook 2016, it connects to exchange server, am able to send emails, however, when i close and reopen outlook 2016, it continuously prompts for user credentials, and does not accept them. However Outlook 2016 v.1001 is unable to connect with HTTP with NTLM. On the domain joined win 10 client machines, outlook 2013 connects fine each time to exchange using HTTP with NTLM auth. In my test env, i have exchange 2013 enterprise installed with both mb, and cas installed on all exchange servers, with AD 2012 R2.
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