Hello,
That happens because your telnet session is waiting for you. You have to authenticate yourself to the pop server with your user and password combination. So when in telnet session (normally the prompt is >) type:
Code:
USER yourusername
PASS yourpassword
LIST
The above will get you a list of available messages which you can read with RETR <number of mail> or delete with DELE <number of mail>.
Telnet is like SSH an interactive client, so if you don't type it doesn't work.
Kind regards,
Eric