问wp_mail()在主域上不起作用，但在子域上起作用

EN

<?php
/

**
 * This file can be used to validate that the WordPress wp_mail() function is working.
 * To use, change the email address in $to below, save, and upload to your WP root.
 * Then browse to the file in your browser.
 */

// Set $to as the email you want to send the test to
$to = "support@XXXXX.com.au";

// No need to make changes below this line

// Email subject and body text
$subject = 'wp_mail function test';
$message = 'This is a test of the wp_mail function: wp_mail is working';
$headers = 'no-reply@xxxx.com.au';

// Load WP components, no themes
define('WP_USE_THEMES', false);
require('wp-load.php');

// send test message using wp_mail function
$sent_message = wp_mail( $to, $subject, $message, $headers );

//display message based on the result.
if ( $sent_message ) {
    // the message was sent...
    echo 'The test message was sent. Check your email inbox.';
} else {
    // the message was not sent...
    echo 'The message was not sent!';
}

<?php
/**
 * This file can be used to validate that the WordPress wp_mail() function is working.
 * To use, change the email address in $to below, save, and upload to your WP root.
 * Then browse to the file in your browser.
 */

// Set $to as the email you want to send the test to
$to = "support@xxxxx.com.au";

// No need to make changes below this line

// Email subject and body text
$subject = 'wp_mail function test';
$message = 'This is a test of the wp_mail function: wp_mail is working';
$headers = 'no-reply@xxxx.com.au';

// Load WP components, no themes
define('WP_USE_THEMES', false);
require('wp-load.php');
add_action('wp_mail_failed', 'print_r');
// send test message using wp_mail function
$sent_message = wp_mail( $to, $subject, $message, $headers );

//display message based on the result.
if ( $sent_message ) {
    // the message was sent...
    echo 'Message Sent';
} else {
    // the message was not sent...
     echo 'Message Not Sent';

}