Once I do that the window keeps coming up like its not accepting the credentials.

I would also like to note that this is not a hybrid environment.

This is the first office 2016 client that I have introduced to our network; all of our other clients are either 2013 or 2010 and are running without any issues.

Any help or advice to help point me in the right direction will be much appreciated.

As it turns out there was a different problem with our exchange server and not allowing us to set up out of office messages.

I found this article today and implemented the change..

Make sure to also clear the credentials from credential manager and check again.

I was wondering if you were able to resolve the automatic replies issue as well Right now, we are still receiving the server is unavailable error message.

My clients issue was the same but connected to a Rackspace Exchange mailbox.

It used to work after the initial setup, but sometime later it developed the issue where it kept asking for the password.

I even looked at the registry keys some were saying keeps the autodiscover failing to the.xml file in the profile directory.

Mac Calendar Keeps Asking For Password