For anyone having this problem, please send me email headers and/or screen shots so I can try and narrow this.
To make it easier to capture the problem, I have a new DEBUG version of Email Users on my web site. You can find it here.
- This DEBUG build will never actually send an email UNLESS wp_mail() has been overloaded in which case there is no way for me to trap that. A red box is containing an “Aborted” message will be displayed when the sending process completes.
- There are checks to see if wp_mail() has been overloaded and visiting the Email Users settings page (Dashboard->Settings->Email Users). A warning will appear at the top of the page if wp_mail() appears to overloaded.
- There is new debug information captured as part of the sending process. It is captured and displayed in Post Boxes at the top of the page after sending an email.
There are a bunch of screen shots in a gallery on this page to help understand this new functionality. What I am looking for is addresses in the CC header being send to wp_mail() and/or in the PHPMailer object.