So I'm having a strange issue, and can't figure out what's not set correctly.
I have a server with exchange server 2010, with IMAP and POP3 services running. Both the IMAP and POP3 client access rules require TLS authentication. Things seem to work fine with IMAP as in the advanced section of Outlook when creating a new account, the drop down menu lists TLS as one of the options, however POP3 only has a checkbox for SSL. When trying to connect with the box ticked, it fails to connect stating that the encryption type is not supported.
I had thought that ticking SSL for POP3 would allow it to connect to exchange, with Exchange having client access rules for POP3 (authentication tab) set to the third one at the bottom (Require TLS). I tried setting it to one of the other options, but it didn't seem to help. The main thing is that I don't want to have an unencrypted connection for POP3. I'm using the correct ports, and forwarding on our firewall, the issue isn't there as far as I can tell.
I've tried with both outlook 2010 and 2007.