Title: Admin-ajax.php issue Last modified: July 10, 2021 --- # Admin-ajax.php issue * Resolved [txtcoke](https://wordpress.org/support/users/txtcoke/) * (@txtcoke) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/) * Hello, I am having an issue with the plugin and admin-ajax.php * My site uses admin-ajax for loading ajax loaders or showing more products on pages etc. * When I for instance press the “more products button”, where products load over admin-ajax, nothing happens. The loader keeps loading infinitely. Then I checked the browser console, and I saw admin-ajax.php is returning 401. * When I clear the plugin cache, everything starts working again, but after some hours, admin-ajax again is 401, and consequently, all loaders that rely on it don’t work, keep loading forever as I mentioned. * I’ve already whitelisted the path on the plugin settings, and it didn’t work. Then, I made a last check, deactivating the plugin, and finally, I could see it was a plugin issue, as the error disappears completely, and things load properly when admin-ajax is called. * Why is that so? I love the plugin, I don’t want to stop using it. What I also don’t understand is why when I clear plugin cache, admin-ajax works properly, and shortly after (some hours), it starts again returning 401 on the browser console. * Note: This issue never happens on the backend, when I am logged in as admin. * How can I solve it? Thank you! Viewing 8 replies - 1 through 8 (of 8 total) * [Harshad](https://wordpress.org/support/users/bornforphp/) * (@bornforphp) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14649398) * [@txtcoke](https://wordpress.org/support/users/txtcoke/) Could you please try to purge the cache and the from WP-Optimize > Cache > Preload, click Preload button to preload all the urls and check if it helps to fix the issue? * Thread Starter [txtcoke](https://wordpress.org/support/users/txtcoke/) * (@txtcoke) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14654551) * Hello I did it to test, but the behavior is the same, after some hours error 403 admin-ajax.php was showing up again, and nothing that relies on ajax was loading… (Sorry in my first message I told 401, but it is 403 error) * [Harshad](https://wordpress.org/support/users/bornforphp/) * (@bornforphp) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14658007) * [@txtcoke](https://wordpress.org/support/users/txtcoke/) Have you performed a conflict test yet? * If not – first, please make a full site backup. * Try deactivating all plugins except for WP-Optimize and see if it is resolved. * If so, reactivate each plugin one at a time until you find the culprit. You can check for the issue between activating each plugin, so you can see which one is causing problems. * Please let us know your findings. * Thread Starter [txtcoke](https://wordpress.org/support/users/txtcoke/) * (@txtcoke) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14673155) * Hello, that method wont work as i mentioned when cached is recently cleared issue is not there. So even though I activate plugin by plugin, I wont find anything as everything will seem to work well as the cache would be new. Issue happens some hours to a day after cache has been flushed. * [Harshad](https://wordpress.org/support/users/bornforphp/) * (@bornforphp) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14678324) * [@txtcoke](https://wordpress.org/support/users/txtcoke/) 403 Forbidden usually occurs when your server is blocking the request, could you please check with your hosting company, if they have any rules added to block the request? * Thread Starter [txtcoke](https://wordpress.org/support/users/txtcoke/) * (@txtcoke) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14678926) * Hello, I’ve already checked it with them. This path is whitelisted on server. I see it comes from the plugin as I had to change the cache plugin, and the issue is not happening with other cache plugins. To be honest I am very sorry because your plugin is the best I used and id like to continue to use it. I would appreciate if you could find out why it happens. I see there were other people who had same issue searching on the forum.. So it seems it didn’t only happen to my site. Thank you * [Marc Lacroix](https://wordpress.org/support/users/marcusig/) * (@marcusig) * [5 years, 1 month ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-14679150) * Hi [@txtcoke](https://wordpress.org/support/users/txtcoke/), * This sounds like the ajax requests are including a `nonce`, which will expire after a few hours, making the request fail. If these requests are for non-logged in users and / or do not have any user-specific content, the use of a nonce doesn’t really make sense. * If you authored the code for these ajax calls, I would recommend removing the use of nonces, **IF the content fetched is not user specific**. * Otherwise you can try reducing the lifespan of the cache to a few hours. * Best, Marc * Thread Starter [txtcoke](https://wordpress.org/support/users/txtcoke/) * (@txtcoke) * [4 years, 9 months ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-15024960) * Can I “whitelist” nonces? Viewing 8 replies - 1 through 8 (of 8 total) The topic ‘Admin-ajax.php issue’ is closed to new replies. * ![](https://ps.w.org/wp-optimize/assets/icon-256x256.png?rev=1552899) * [WP-Optimize – Cache, Compress images, Minify & Clean database to boost page speed & performance](https://wordpress.org/plugins/wp-optimize/) * [Frequently Asked Questions](https://wordpress.org/plugins/wp-optimize/#faq) * [Support Threads](https://wordpress.org/support/plugin/wp-optimize/) * [Active Topics](https://wordpress.org/support/plugin/wp-optimize/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/wp-optimize/unresolved/) * [Reviews](https://wordpress.org/support/plugin/wp-optimize/reviews/) ## Tags * [admin-ajax](https://wordpress.org/support/topic-tag/admin-ajax/) * 8 replies * 5 participants * Last reply from: [txtcoke](https://wordpress.org/support/users/txtcoke/) * Last activity: [4 years, 9 months ago](https://wordpress.org/support/topic/admin-ajax-php-issue-3/#post-15024960) * Status: resolved