Investigate MailPoet

[nate-allen]

It looks like MailPoet can be setup to send emails without using wp_mail. Look into how it does send email, and if we can disable that feature. If not, we may need to add the plugin to the deny list.

[NickGreen]

Adding plugin to the denylist in the short term. If this issue turns up a better solution, feel free to remove it as needed.

[gin0115]

The mailer options are saved in the {prefix_}mailpoet_settings table.

---

You can force the mailer to use PHP by setting

• smtp_provider = server.

• mta you need to set the method value as PHPMail

  a:14:{s:22:"mailpoet_api_key_state";a:3:{s:18:"access_restriction";s:0:"";s:4:"data";a:1:{s:11:"is_approved";s:5:"false";}s:5:"state";s:11:"check_error";}s:14:"authentication";s:1:"1";s:10:"encryption";s:0:"";s:8:"password";s:3:"pgq";s:5:"login";s:2:"gq";s:7:"api_key";s:0:"";s:10:"secret_key";s:0:"";s:10:"access_key";s:0:"";s:6:"region";s:9:"us-east-1";s:4:"port";s:4:"2424";s:4:"host";s:14:"smtp.null.void";s:16:"mailpoet_api_key";s:0:"";s:9:"frequency";a:2:{s:8:"interval";s:1:"5";s:6:"emails";s:2:"25";}s:6:"method";s:7:"PHPMail";}

  ...

  Array
  (
  [mailpoet_api_key_state] => Array
      (
          [access_restriction] => 
          [data] => Array
              (
                  [is_approved] => false
              )
  
          [state] => check_error
      )
  
  [authentication] => 1
  [encryption] => 
  [password] => pgq
  [login] => gq
  [api_key] => 
  [secret_key] => 
  [access_key] => 
  [region] => us-east-1
  [port] => 2424
  [host] => smtp.null.void
  [mailpoet_api_key] => 
  [frequency] => Array
      (
          [interval] => 5
          [emails] => 25
      )
  
  [method] => PHPMail
  )

• Setting the method as PHPMail is the only change needed.

There is another DB key called web_host, this can be set to manual (probably no needed)

---

Or you can set fake SMTP using

• smtp_provider = manual

• mta you will need to update

  • host as some fake host
  • port as some fake port
  • login as some fake username
  • password as some fake password

  • method as SMTP

    a:14:{s:22:"mailpoet_api_key_state";a:3:{s:18:"access_restriction";s:0:"";s:4:"data";a:1:{s:11:"is_approved";s:5:"false";}s:5:"state";s:11:"check_error";}s:14:"authentication";s:1:"1";s:10:"encryption";s:0:"";s:8:"password";s:3:"pgq";s:5:"login";s:2:"gq";s:7:"api_key";s:0:"";s:10:"secret_key";s:0:"";s:10:"access_key";s:0:"";s:6:"region";s:9:"us-east-1";s:4:"port";s:4:"2424";s:4:"host";s:14:"smtp.null.void";s:16:"mailpoet_api_key";s:0:"";s:9:"frequency";a:2:{s:8:"interval";s:1:"5";s:6:"emails";s:2:"25";}s:6:"method";s:4:"SMTP";}

    ...

    
    Array
    (
    [mailpoet_api_key_state] => Array
    (
        [access_restriction] => 
        [data] => Array
            (
                [is_approved] => false
            )
    
        [state] => check_error
    )

  [authentication] => 1 [encryption] => [password] => pgq <<== [login] => gq <<== [api_key] => [secret_key] => [access_key] => [region] => us-east-1 [port] => 2424 <<== [host] => smtp.null.void <<== [mailpoet_api_key] => [frequency] => Array ( [interval] => 5 [emails] => 25 )

  [method] => SMTP <<== )

[BrianHenryIE]

I wasn't aware of that hook solution.

I approached a similar problem by loading the PHPMailer class early and replacing it with a subclass of my own where I overrode the send method.

https://github.com/BrianHenryIE/bh-wp-one-click-list-unsubscribe-mailto-header/blob/50fbdf36ae028d0d09e8849ef9ffd0da170980bf/src/Integrations/class-mailpoet.php#L50

https://github.com/BrianHenryIE/bh-wp-one-click-list-unsubscribe-mailto-header/blob/50fbdf36ae028d0d09e8849ef9ffd0da170980bf/src/API/class-phpmailer-intercept.php#L7

Didn't really test it much.