I have my own Mailhosting, and am moving servers. Thunderbird works fine with the new Server IP. However, Apple Mail seems to fail and to silently ignore the new server. I am using Courier IMAP and ...
Any attempt to connect to a server over port 143 is blocked by the OS. I've verified it's not my connection; other computers on the network can see the port just fine. I've replicated the problem on a ...