- 1). Download the free software program PuTTY, preferably to your computer's desktop, using the link in the Resources section. PuTTY doesn't have a traditional installation process. Instead, you download the actual application directly onto your computer. Make a note of where you download the putty.exe file.
- 2). Start PuTTY on your computer by double-clicking the putty.exe file. Enter the domain name or Internet protocol (IP) address of your SMTP server in the "Host Name (or IP address)" field, and then enter "25" in the "Port" field. Click on "Raw" beneath "Connection type:," and click on the "Open" button.
- 3). Watch for a black window with a response from your SMTP server. It should display wording such as "220 mail.example.com ESMTP." This means you connected successfully to your SMTP server and it responded with a greeting message. If the window appears only briefly, then double-check your SMTP server details and your Internet connection. If your Internet connection works and the details are correct, then the SMTP server isn't running.
- 4). Submit a test message to the server by typing the commands that follow this paragraph. Use uppercase letters as shown in the commands, but most SMTP servers accept only lowercase letters. Press the "Enter" key at the end of each statement. Wait for a response from the server before proceeding to the next line. Replace "youremailaddres@example.com" with your email address. These are the commands:
HELO example.com
MAIL FROM:<youremailaddres@example.com>
RCPT TO:<youremailaddres@example.com>
DATA
From: youremailaddres@example.com
To: youremailaddres@example.com
Subject: Test
This is a test.
.
QUIT
The SMTP server will respond to each statement you type with a line starting with "250," except for the DATA command, which will illicit a "354" response. Once you enter the "QUIT" command, the server will disconnect. If you mistype, use your computer's "Backspace" key to erase the mistake and retype the command. - 5). Check your email for the test message. You may need to check in your email's spam folder because the message will not include some elements. It should contain enough elements, however, to be delivered.
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