How to test if your ISP is blocking the use of third party SMTP servers

The purpose of this article is to assist our clients in testing to see if their ISP is blocking the use of third party SMTP servers (servers used to send email). We'll do our best to make this as easy as possible by explaining the details of the procedure. You'll be opening a DOS prompt window and at most entering 4 simple commands.

1. Click Start Menu in Windows then select "Run...".
2. A new window will pop up with a text box where you'll type in "cmd" (without the quotes).
3. Now click the "OK" button.

This will open up a DOS prompt that looks similar to this C:\>. You can then type commands to the right of this prompt. Please type the commands that are shown as bold blue text in the Windows DOS Prompt box below. The other text shown will be similar to what you should see the computer respond with.

Whenever you see $DOMAIN, please change it to your domain name. For example, if your domain is ez2ba.com, the first thing you'll type will actually be:
C:\> telnet mail.ez2ba.com 110
Just the same you'll be using your email box user name (the part before the @ symbol) in exchange for $USERNAME and your email box password in exchange for $PASSWORD.

	Windows DOS Prompt C:\> C:\> telnet mail.$DOMAIN.com 110 +OK $DOMAIN.com POP3 Server (Version 1.020h) ready. user $USERNAME +OK please send PASS command pass $PASSWORD +OK 0 messages ready for $USERNAME in /home/user/doamin-mail/$USERNAME quit +OK $DOMAIN.com POP3 Server (Version 1.020h) shutdown. Connection to host lost. C:\>

If your ISP is blocking the use of our SMTP (sending) servers, you'll get an error on the first prompt. The error may looks something like this, "C:\>telnet mail.$DOAMIN.com 110
Connecting To mail.$DOMAIN.com...Could not open connection to the host, on port 110: Connect failed". If you get this error, then you should contact your ISP and ask them to help set up your SMTP server settings for your email program.

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