Unable to send email Error:550

Unable to send email Error:550

I'm unable to send email with the error details

, ERROR CODE :550 - 5.5.1 Server IP 136.143.188.52 listed as abusive. See
            http://spamauditor.org/best-practices/ip-reputation/ for more information..
            Protection provided by MagicSpam 2.2.1-3 http://www.magicspam.com