Recently MDaemon that installed on Windows Server 2003, ceased to send or receive messages from\to some mail servers. As it turned out, the problem is in the obsolete SSL\TLS protocols on Windows Server 2003.

Symptoms (cut from log):

Time goes by, and Windows XP and Windows Server 2003 is not getting any younger. At the same time, security standards are developing independently of these legacy operating systems. Using them in your infrastructure, you not only put your entire it system under attack, but sometimes just lose functionality.

Here is example when MDaemon cannot establish SSL connection with other mail servers or clients (both while sending and receiving mail)

If you are using MDaemon with Windows Server 2003, you may experience problems with delivering or receiving mail from other mail servers.