When I pinged my mailserver from the command prompt using:
telnet mail.mydomain.com 25I got the error
Telnet is not a recognized command. I looked for a workaround and then found that Telnet was unchecked by default in Windows. Once i checked it, it started working.
Solution:
TELNET communicates with the peer (telnet server) in clear text.
This is a security hazard compared to say the SSH connect. To this end, the telnet client on windows is disabled by default. This often comes as a surprise and many sites describe the steps to get it working,
you seem to have found them already 🙂
For normal purposes, it would be a better option to use SSH (PuTTY or freeSSHd if you want to connect to a Windows machine).