Location rules select throws admin-ajax.php 400 error

• jimmya

• February 23, 2023 at 6:30 pm

Hi there,

I’m trying to change a Location rule for a field group, when I click the select input under “Show this field group if” to select anything (e.g. “Page”) the second select turns gray and doesn’t show anything.

If I check the browser Network tab I see the AJAX petition throwing a HTTP 400 error and I can’t understand why. The response from “admin-ajax.php” is “0”.

My temporal workaround is to select “Page”, update/save the field group, then go back and select the page that I want to apply the rule to, but this didn’t happened before in another projects I worked on with ACF so I’m curious about that could be happening here.

Example (in this case using “Post” but happens with any other selected item):

• jimmya

• February 23, 2023 at 7:04 pm

The same thing happens when I’m trying to create a Group type.

It shows the loader, then throws the AJAX error, then the loader disappears and nothing happens. I have to update/save the field group and then the inputs appear after the page was reloaded. It’s really annoying.

• John Huebner

• February 24, 2023 at 3:55 pm

Something on the server is interfering with the ajax request. Look at your server php error logs to see if you can find anything there.

• jimmya

• February 25, 2023 at 11:06 pm

I don’t see anything about it in my logs. I will try to fix it this weekend and keep you posted about what’s the issue.

• jimmya

• February 25, 2023 at 11:39 pm

So, I did a quick research and apparently the file “/wp-admin/admin-ajax.php” requires the action to have the string “wp_ajax_” prepend to the action (lines 176-178 and 191-193 in that file). The ACF plugin doesn’t seem to prepend that string (check previous screenshots, where action = “acf/field_group …”), any quick solutions for this?

• John Huebner

• February 26, 2023 at 10:31 am

I am not seeing this error, the issue is not in ACF.

WP automatically adds wp_ajax_ to run the action, this is not something that is supplied on the client side.

Please ensure that you have error logging turned on https://wordpress.org/documentation/article/debugging-in-wordpress/

Deactivate other plugins to see if you can figure out what is interfering. Also check your theme if it is not another plugin. If this fails then try uninstalling and reinstalling ACF, you might have a corrupted file.