Support » Plugin: Better Section Navigation Widget » Fatal Error: Call to undefined function is_plugin_active()

  • Resolved siteoctopus


    After updating the plugin to the most recent version, I get this error on all pages (including the admin dashboard)

    HP message: PHP Fatal error: Uncaught Error: Call to undefined function is_plugin_active() in <<WORDPRESS PATH>>/wp-content/plugins/better-section-navigation/exclude-pages.php:271

    For the moment I’ve commented out the require_once that includes exclude-pages.php but of course that’s not a permanent solution.

    PHP Version: 7.1.9
    WP Version: 4.9.8

Viewing 8 replies - 1 through 8 (of 8 total)
    this version breaks WP with HTTP 500

    I’m getting a fatal error after upgrading as well. Running WP 4.9.8 and PHP 7.0.31.

    Thread Starter siteoctopus


    After the most recent update the plugin is still broken. This time it causes an error when viewing the page/post editor:

    PHP message: PHP Fatal error: Uncaught ArgumentCountError: Too few arguments to function wp_kses(), 1 passed in /WORDPRESS PATH/wp-content/plugins/better-section-navigation/exclude-pages.php on line 208 and at least 2 expected in /WORDPRESS PATH/wp-includes/kses.php:526

    Again, this can be fixed by commenting require_once 'exclude-pages.php';

    • This reply was modified 4 years, 3 months ago by siteoctopus.
    Plugin Author cornershop


    Hi there! Sorry for the delay.

    We fixed the first issue (“Call to undefined function is_plugin_active()”) earlier in August, and then fixed the second one (“Too few arguments to function wp_kses()”) on 8/24, so everything should be working now.

    I don’t know exactly why there were so many issues in that file, but the wp_kses() issue is related to a change in PHP 7.2: that same error used to be non-fatal, and so it could easily fly under the radar during development, but the PHP team has decided to crack down on it in the newest release of PHP.

    thank you! I will give it a try in my testing environment.

    FYI, this is NOT related to PHP 7.2 as I have the issue with PHP 7.0.32

    Plugin Author cornershop


    Hi @audioscavenger

    Just checking to see how things went on your testing environment. Let us know if there are any errors we should investigate — and feel free to email if you have additional information to share about the issue.


    sorry for late reply

    thank you the error is gone
    you can close the thread

    Plugin Author cornershop


    Thank you!

Viewing 8 replies - 1 through 8 (of 8 total)
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