CM Answers (CMA) - How to debug mailing issues when you don't receive any emails from the plugin


Route of the email from WordPress to receiver

  1. When our plugin wants to send an email it's calling the standard wp_mail() function. Beyond that our plugin's role is over.
  2. WordPress by default will use the standard PHP mail() function to delegate sending email. PHP will use the to the localhost's mail daemon as sendmail or postman (on Linux servers) depending on the php.ini configuration.
  3. If you're using some extra SMTP support plugins in your WordPress then WordPress will delegate sending email to this plugin. In most cases it will connect with the external SMTP server using the settings and login credentials that you've provided to this plugin.
  4. The daemon or the SMTP server will queue the email and try to deliver by connecting with the receiver's mail server. It will try several times in case the target server is unavailable. The email can be rejected or can be delivered after several minutes or even hours.

I don't receive emails from CM plugin

There are a lot of reasons why you may not receiving emails from the plugin:

  • Your server environment may be not configured properly.
  • You've installed a SMTP support plugin for WordPress but it hasn't been setup properly.
  • Your mailing provider doesn't support empty "To" header.
  • You didn't setup properly the mailing options in our plugin.
  • Your mail server or the receiver's mail server applies some strict security policy or other restrictions and rejects the email.
  • There's a conflict with the other plugin.

Before contacting the CM support please follow the instructions below.

How to check what's the issue?

  1. First install a WordPress plugin that will log the outgoing emails. We also recommend to use our CM Email Tools plugin in order to configure the SMTP connection, log outgoing emails and debug why it's not working.
  2. In order to check if this is our plugin fault or just your mail server doesn't work please send an email from outside the plugin.
    1. Probably your SMTP supporting plugin have an option to send a testing email so send it to the different receivers which are using different email providers. Sometimes emails aren't delivered just to your own server.
    2. Also try to send emails from your other plugins.
  3. If you're not receiving any emails then probably your SMTP supporting plugin or your sendmail daemon is not configured properly. Contact with your system administrator.
  4. If you are receiving the emails but not from our plugin then try to log outgoing emails using a WordPress plugin mentioned in (1).
  5. If the emails from our plugin are being properly logged in the outgoing mail log then it seems that your mail daemon or SMTP server is rejecting it. Please contact with your mailing provider and ask why the email might be rejected. Sometimes the email providers apply a security policy and limit the BCC receivers in order to reject spammers or reject emails with empty "To" header so you can ask also if the server supports sending bulk emails with empty "To" header and multiple receivers in multiple "BCC" headers.
  6. When emails from our plugin are not being logged in the outgoing mail log then double-check your mailing settings in our plugin's settings page. Also please try to make plugin send an email to a different email address in a different domain (in case your email provider may filter emails from Wordpress for some reasons).
  7. If nothing left - contact our CM support team.