I have searched and read dozens of articles but haven't seen anything that specifically matches my case.
I have two sites, chicago and ohio. Each site has a exchange 2010 server, and users are on outlook 2007 or 2010. Three weeks ago, the ohio team needed an external IP and port 443 for it. They intentionally borrowed the one used for the exchange server. Two hours later a different external IP and port 443 for it was freed up. Since that moment of changing the IP, 4 users out of 30 in ohio have had trouble connecting to the server with their outlook clients. OWA and email on phones has not been affected.
The trouble that they have had is outlook keeps prompting these 4 users for username/password. We do have outlook anywhere enabled, and autodiscovery for 2010 almost always tries to use that, but switching users to OO or not to use OO doesn't appear to make a difference, the password popup keeps appearing. I have tried creating a new profile, but that doesn't seem to be a permanent fix. All 4 users have laptops and have tried this from home, it seems to be worse when trying to login at home. Those who use OO get the popup, so I had them connect via a PPTP vpn, same problem, so I had them connect with a SSL vpn, same problem. One recent change I made was to move the firewall policy for exchange higher in the order list, in hopes that it made a difference.
Any ideas? I am 90% sure that changing the IP/port did this? users say thats when they last got an email. I deployed a new laptop to one user and that fixed it, so far. Do I need to delete a whole windows profile?