I just upgraded my exchange from 2007 to 2013, well, I migrated, as it's a new server.
Some clients are fine, but some are getting this error message. it's attached.
How do I resolve this, as I did a google search, and I couldn't really find anything. I found one article, which I did install the exchange certificate on this machine with this error, but it's still not working.
I tried this, but no success:
The client is running outlook 2013 RTM. Other are running 2010, with either SP1 or Sp2.
I do know that the 2010 need to have a certain KB that makes it compatible, but this machine is using outlook 2013. When using the outlook web app, it allows the user to log in with no errors.