I am currently developing a minor dynamic website. Towards the end of the development I was stress-testing some of the dynamic functionality.
Unfortunately I am getting occasional 404 errors from admin-ajax.php.
The request seems to be sent and processed because on refresh of the page I can see the updates. However it is a bad user experience because the user’s page just stalls.
After a little troubleshooting, mainly with crude debug statements from admin-ajax.php into HTTP headers, I have noticed that admin-ajax.php is not even entered.
At the moment I am not sure whether the error is related to one of the WordPress plugins I am using or whether it is due to my webhost.
There are no visible errors in weblogs nor in error_log.
One thing I noticed that a new incognito browser window resolved the issue.
This made me suspicious of cookie issues. I manage to narrow it down to the PHPSESSID cookie. Clearing it resolved the issue. The 404 error from admin-ajax.php is gone… for a while at least.
I recommend using the excellent Eat This Cookie extension If you are using Chrome or Brave browser.
The search continues…
The Google empire has released yet another (Beta) service which this time is an instant messenger network and client