Out going mail not sending in mavericks

Question

I've had this problem since upgrading to mavericks, mail not sending and the sntp server showing off line.
I"VE FIXED IT!!!!
Guys hope this helps, the ports show default - 25, 465, 585 in edit smtp settings. Check the next box down - use this port and type in 25, I know its in the default list but its sent my mail when using the custom port.
Hope this helps, I spent all day yesterday on to my server supplier and onto chat with Apple in US but couldnt solve it.
Best of luck!!

Answer 1

For the past few weeks, I have been noticing a similar problem: access to 11 email accounts, and three domains, is blocked on occasion. According to my web hosting company, this is happening because some process was attempting to connect via port 585, an insecure IMAP port; and that an automatic firewall rule was invoked to block those attempts. The blocking would last for about one hour after the last attempt was made to connect.
I'm running Mavericks. If I quit Mail, then restarted one hour later, the problem was resolved. UNTIL Mail attempted to connect to my mail servers, upon which the blocks were triggered again.
I downloaded Little Snitch. It told me, unsurprisingly at this point, that three email accounts were attempting to use port 585 to connect to their mail server. But I DON'T USE IMAP with those accounts! Why Mail is attempting to connect to a port which I haven't configured it to use is the puzzle.
The solution for me: tell Little Snitch to deny any access via port 585.