Category: eDM

http://www.campaignmonitor.com/css/

http://www.apsis.com.hk/

Gmail
https://mail.google.com/support/bin/answer.py?answer=81126#thirdparty

Yahoo
http://help.yahoo.com/l/us/yahoo/mail/postmaster/bulkv2.html

Hotmail:
https://support.msn.com/eform.aspx?productKey=edfsjmrpp&page=support_home_options_form_byemail&ct=eformts&st=1&wfxredirect=1

If you get this error when you are trying to send email to Yahoo. It is very likely that your server ip is black-listed.

You can contact yahoo postmaster by filling in the form here: http://help.yahoo.com/l/us/yahoo/mail/postmaster/errors/?referrer=blog.my-helper.com

Another easier solution is to change your server IP.

The problem could be solved by:

• Adding Message-ID to the header
• Encoding the subject in base64 form:
  $subject = ‘=?utf-8?B?’ . base64_encode(‘EMAIL SUBJECT’) . ‘?=’;
• Using php mail() function instead of PHPMailer