We are in the midst of deploying an Exchange 2013 SP1 CU5 environment and have run into some issues. Currently there is a good coexistence between a single Exchange 2007 server and the 5 2013 servers. Mail is flowing through 2013 and then being relayed to 2007 when necessary.
We have a number of Server 2003 Terminal Servers. On two separate machines, both running the lastest rollups of Outlook 2010, any user with a 2013 mailbox receives a password prompt after launching Outlook. It is trying to connect to one of the two CAS, fills in the user's account, and will not accept any password. In addition, a window pops up behind stating "There is a problem with the proxy server's security certificate. the name on the security certificate is invalid or does not match the name of the target site mail.pvschemicals.com. Outlook is unable to connect to the proxy server. (error code 0)." 2007 mailboxes are not affected.
We have checked pretty much everything that we can think of. Virtual Directories are good, certificate is good, etc. The strange thing is that only happens on 2003 TS machines, so I have to think that it's related. Our 2008 TS' are just find.
We have applied the 2003 SHA2 certificate hotfix.