How do I find out my mail server blacklisted?

Q. How do I find out if my e-mail server IP address is blacklisted?

A. First make sure you are not source of spam:

a) You have correct reverse IP address mapping

b) Your mail server is not open to spammers

mxtoolbox offers test that will check a mail server IP address against 147 DNS-based blacklists. (Commonly called Realtime blacklists, blocklists, DNSBLs or RBLs). If your mail server has been blacklisted, some email you send may not be delivered. Blacklisting is a common way of reducing spam.

Step # 1: Find out your mail server ip address

For example if your domain name is
$ host -t mx nixcraft.comOutput: mail is handled by 10

Get IP address of this host:
$ host -t a has address

Step # 2: Now visit mxtoolbox site and enter a mail server IP address

=> Visit mxtoolbox web site.
=> Enter IP address

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🐧 9 comments so far... add one

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9 comments… add one
  • John Chow Feb 10, 2009 @ 20:56

    As a Newbie, I am always searching online for articles that can help me. Thank you

  • Yonis Khan Feb 10, 2009 @ 21:18

    amazing stuff thanx :)

  • S Smith Feb 26, 2009 @ 3:40

    Thank you for your help!

  • Slots Mar 19, 2009 @ 16:43

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  • Matthew S Oct 26, 2009 @ 14:57

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