CREATE DKIM KEYS and DNS Resource Record: ========================================= To create DomainKeys Identified Mail keys, visit: http://dkim.worxware.com/ ... read the information, fill in the form, and download the ZIP file containing the public key, private key, DNS Resource Record and instructions to add to your DNS Zone Record, and the PHPMailer code to enable DKIM digital signing. /*** PROTECT YOUR PRIVATE & PUBLIC KEYS ***/ You need to protect your DKIM private and public keys from being viewed or accessed. Add protection to your .htaccess file as in this example: # secure htkeyprivate file order allow,deny deny from all # secure htkeypublic file order allow,deny deny from all (the actual .htaccess additions are in the ZIP file sent back to you from http://dkim.worxware.com/ A few notes on using DomainKey Identified Mail (DKIM): You do not need to use PHPMailer to DKIM sign emails IF: - you enable DomainKey support and add the DNS resource record - you use your outbound mail server If you are a third-party emailer that works on behalf of domain owners to send their emails from your own server: - you absolutely have to DKIM sign outbound emails - the domain owner has to add the DNS resource record to match the private key, public key, selector, identity, and domain that you create - use caution with the "selector" ... at least one "selector" will already exist in the DNS Zone Record of the domain at the domain owner's server you need to ensure that the "selector" you use is unique Note: since the IP address will not match the domain owner's DNS Zone record you can be certain that email providers that validate based on DomainKey will check the domain owner's DNS Zone record for your DNS resource record. Before sending out emails on behalf of domain owners, ensure they have entered the DNS resource record you provided them. Enjoy! Andy PS. if you need additional information about DKIM, please see: http://www.dkim.org/info/dkim-faq.html