知識庫

From time to time you may need to perform an operation called "telnet". You can use TELNET to check connections to certain ports on a server.

To begin you press the "START" button on your Windows taskbar, (found in the lower left corner of your Windows screen), this should bring up your Start Menu.
Find "Run" and enter the letters "CMD" (without the quotes) if you have an older version of Windows, otherwise just type in "CMD.EXE" and press the ENTER key.

This will open a black command prompt screen, on it you will find a small flashing cursor. To run a TELNET on your email to check for connection to sending (SMTP), type the following in the black command prompt screen:

telnet cp1-cl1.serverclienti.com 25

(you can change the port to which ever port you need to check, commonly 25 465), then press "ENTER" again.

You should receive in return a screen something to the effect of:

220-cp1-cl1.serverclienti.com ESMTP Exim 4.93 #2 Fri, 24 Jul 2020 10:41:44 +0200
220-We do not authorize the use of this system to transport unsolicited,
220 and/or bulk e-mail.

A return with 220 codes means you have connected to the server, the exact verbiage you get back will be determined by your host and vary.

Being able to connect to the server means the server is not an issue if you are having a problem sending, areas to look at would be your ISP, your Mail Program, your Program Settings, Firewalls etc.

You can TELNET to any port you choose, some ports may be blocked and some hosts will block you if you try too many blocked ports.