Problem sending to certain recipients - Spamauditor.org / magicspam.com

Problem sending to certain recipients - Spamauditor.org / magicspam.com

When I try to email certain customers I get the following error.

Server IP 135.84.80.196 listed as abusive. See http://spamauditor.org/best-practices/ip-reputation/ for more information. Protection provided by MagicSpam 2.1-2 http://www.magicspam.com

Help?