Facing problem with WordPress pingbacks? You are not alone. I have worked with several clients so far who experienced the exact same problem. Many website owners consider pingbacks and trackbacks as an important SEO factor. So it is good to make sure these things work correctly on a WordPress installation.
There has been a known issue regarding WordPress pingbacks since WP version 2.7. The developers of WordPress don’t want to make adjustments to resolve the issue as the current settings run smoothly under most circumstances. For more in-depth research into the matter, please see this ticket on WordPress Trac.
To simply put, in most cases the pingback problem is not due to the server or website misconfiguration. It is due to a TimeOut variable for the ping (since 2.7, this value is 0.01 seconds.) This time limit of 0:01 seconds may not work great for some websites. Some servers do not manage to ping within 0.01 seconds.
Solution to the Pingback Problem
The timeout value of WordPress pingback can be found in the file “wp-includes/cron.php” (not to be confused with the
wp-cron.php). In line 229 you will find the value for the timeout.
$ cron_url = get_option ('siteurl'). , /wp-cron.php?doing_wp_cron '; wp_remote_post ($ cron_url, array (, timeout '=> 0.01,, blocking' => false, 'sslverify' => apply_filters (, https_local_ssl_verify ', true)));
Now you need to change the current timeout value (0.01) to 1 and see if it fixes the issue for you.
$ cron_url = get_option ('siteurl'). , /wp-cron.php?doing_wp_cron '; wp_remote_post ($ cron_url, array (, timeout '=> 1,' blocking '=> false,' sslverify '=> apply_filters (, https_local_ssl_verify', true)));