wp-mail

Yes, wp_mail_from_name filter is a correct way to change the “From” name in emails sent by WordPress. It should not cause any issues with other plugins.

It looks like you are setting the $emailto variable after the place you are using it.

You have to provide the absolute path for your included image, as the receiver of the email does not have a file “signature.gif” in a folder “img” (that’s where the client is going to search it) Replace $message .= “<img src=”https://wordpress.stackexchange.com/questions/266338/img/signature.gif”>”; with $message .= “<img src=”http://yourwebsite.com/PATH/TO/img/signature.gif”>”; Where yourwebsite.com is your website’s domain followed by the … Read more

The standalone script will not load WordPress, so it doesn’t have a wp_mail() function. WordPress has its own built-in Ajax handlers which you can leverage and have access to all WordPress functionality within those Ajax calls.

Reference link click here. Using below code you can send the mail with html format. $to = ‘[email protected]’; $subject=”The subject”; $body = ‘The email body content’; $headers = array(‘Content-Type: text/html; charset=UTF-8’); wp_mail( $to, $subject, $body, $headers ); // For attachment $attachments = array( WP_CONTENT_DIR . ‘/uploads/file_to_attach.zip’ ); $headers=”From: My Name <[email protected]>” . “\r\n”; wp_mail( ‘[email protected]’, … Read more

Filter ‘phpmailer_init’, not ‘wp_mail’. To prevent sending the mail out reset the PHPMailer object. Prototype (not tested): add_action( ‘phpmailer_init’, ‘wpse_53612_conditional_mail_stop’ ); function wpse_53612_conditional_mail_stop( $phpmailer ) { ! my_condition() and $phpmailer = new stdClass; }

Here is a better WordPress SMTP mailer. https://wordpress.org/plugins/postman-smtp/

Using wp_mail() function outside of WordPress and through PHP CLI

Yes. You can. There is several filters what you mentioned in your question. You can do it with WP Mail SMTP plugin. This plugin have multiple settings such as: Sender Name, Sender Email. To get it to set the envelope sender as well, you have to turn on the “Return Path” option. This stuff working … Read more