Support » Plugin: Events Manager » “A variable mismatch has been detected.”

  • tjalexander70


    Events Manager Version: 5.9.5
    WordPress Version 5.0.3

    A user on my website is repeatedly getting the error message “A variable mismatch has been detected.” when trying to add an event.

    They previously added events without a problem and I am not able to recreate the problem.

    I have also looked in out server’s error logs and found nothing.

    Is there anything that could be causing this problem?

    The page I need help with: [log in to see the link]

Viewing 10 replies - 46 through 55 (of 55 total)
  • Solved the problem by disabling rtmedia which also limits upload sizes. Furthermore, for me it wont fix the problem to run on php 7.2 or any other version.

    @mickaelmaur posted a dump with rtmedia installed as well

    • This reply was modified 8 months, 3 weeks ago by micaphonic.
    • This reply was modified 8 months, 3 weeks ago by micaphonic.

    I changed the image-sizes in several ways after the suggestion from @kristianngve. But the error still occurs!

    Only a rollback to WordPress 5.0 solves the problem on my system.

    I am upset now. Since months users are describing this problem. Is there any support at all?

    I am really not convinced to invest in the pro-version.

    Same issue here.
    Have updated wp and all plugins to latest as of July 12, 2019.
    Changing php version (7.2) and downgrading wp not an option.

    Looks like this issue has been outstanding for five months. Ouch.

    Ok! On to the next event system. This one cost me two days of fudging around.

    I do not understand why “unregistered” is not a user group in wp. They are real people and we often want their input. Looks like it will be too challenging with this plugin.

    Most important, I am unable to modify the meta query for events. Clueless today about why, but know that is essential for my site. I filter by a custom field.

    Uninstalled for now.




    I am receiving:

    A variable mismatch has been detected.

    When submitting an event on the frontend running PHP 7.0 or PHP 7.1.

    Has there been any resolution to this?

    Plugin Author Marcus


    Hi Everyone,

    Sorry for not having replied sooner here. I have tested out this issue, and I’m not able to reproduce it myself. I have image sizes below the image I try to upload via the front-end and I get the appropriate error message.

    I’ve searched the WordPress core code for the presence of that error message, and whilst I found it, I can’t figure out under what circumstances this would get triggered by an image upload.

    I would need to take a closer look at someone’s site so that I can reproduce the error. Upon doing so, hopefully, I can reproduce it locally or debug it on that specific website.

    If anyone would like me to take a look, please get in touch either via the WordPress slack and privately DM me, or send a message via our contact us page, referencing this forum thread url and your username on

    I think I have the solution. The problem occurs when the URL of your editing form has the querystring “action=”. In my case it’s “action=edit”.

    The prolem happens because the form sets the “action” attribute without resetting the querystring completely AND it contains an hidden input having name=”action” and value “event_save”.

    The form action is set this way (file templates/forms/event-editor.php line 26):
    action="<?php echo esc_url(add_query_arg(array('success'=>null))); ?>"

    The new WordPress checks if GET and POST inputs match and, in case of mismatch, it throws the error.

    So the form posts to an URL ending with ?action=edit but it also contains the “action” input set to event_save, so WordPress stops the procedure for security reasons.

    If you edit (waiting for the fix) the file templates/forms/event-editor.php at line 26 and change the action value to:

    action="<?php echo esc_url(add_query_arg(array('success'=>null,'action'=>null))); ?>"

    you make it work!

    • This reply was modified 1 month, 2 weeks ago by itestense.
    • This reply was modified 1 month, 2 weeks ago by itestense. Reason: line numbers
    Plugin Support timrv


    @itestense, Thanks for checking on the issue. I have forwarded this to our Devs so they could test on the issue based from your suggestion.

    Just some additional information, Could We perhaps know the versions of the following? This way We could set-up the same environment.
    WP version:
    PHP version:
    EM version:

    WP version: 5.3
    PHP version: 7.1.29 (and also 7.0.33)
    EM version:

    Plugin Author Marcus


    Thanks @itestense that gives us something to go on. I’ve written to your email to try and get some help reproducing the issue, otherwise we’ll test the fix to make sure it won’t break things and implement it regardless.

    I also sent you an email with further details.


Viewing 10 replies - 46 through 55 (of 55 total)
  • You must be logged in to reply to this topic.