Fatal error: Class WP_Taxonomy not found in taxonomy.php line 384

  • briancbeers

    (@briancbeers)


    9 years ago

    I see that this error happened for a few people on 4.7, and I tried the solutions suggested.
    1) Replacing wp-settings.php
    2) Manually updating the site. This means deleting folders wp-admin and wp-includes, and every file except wp-config.php. Then uploading them again via FTP

    These did not fix the error.

    I also edited wp-settings.php swapping lines 193 & 194
    require( ABSPATH . WPINC . ‘/taxonomy.php’ );
    require( ABSPATH . WPINC . ‘/class-wp-taxonomy.php’ );

    changing them to

    require( ABSPATH . WPINC . ‘/class-wp-taxonomy.php’ );
    require( ABSPATH . WPINC . ‘/taxonomy.php’ );

    The logic for this is that perhaps Class WP_Taxonomy had to be declared before it could be used in taxonomy.php.

    But this didn’t work either.

    At this time I have restored from my backup, and the site is running on 4.6.6.

Viewing 6 replies - 1 through 6 (of 6 total)
  • Moderator James Huff

    (@macmanx)

    9 years ago

    You’ve done everything to rule-out a core file problem, so that would suggest a problem introduced by a plugin or theme.

    Upgrade to WordPress 4.8, after which you’ll likely encounter the error again, then try manually resetting your plugins (no Dashboard access required). If that resolves the issue, reactivate each one individually until you find the cause.

    If that does not resolve the issue, access your server via SFTP or FTP, or a file manager in your hosting account’s control panel, navigate to /wp-content/themes/ and rename the directory of your currently active theme. This will force the default theme to activate and hopefully rule-out a theme-specific issue (theme functions can interfere like plugins).

    Thread Starter briancbeers

    (@briancbeers)

    9 years ago

    I had disabled all plugins before rolling back to 4.6.6, but it made no difference.

    I will try disabling the theme tomorrow, but I am both sceptical and horrified that a bit of code in a theme might be the cause of a compilation error in the WordPress core.

    Moderator James Huff

    (@macmanx)

    9 years ago

    We see sites taken down by function conflicts from plugins and themes all the time. Overall, it depends on the quality of the plugin or theme.

    Think of it this way, plugins and themes are supposed to fundamentally extend or change the functionality of the site, and sometimes that doesn’t work out in a positive way.

    With that said, we see it often around here because these are *support* forums, people don’t come here with their success stories. Normally, you’ll never run into a problem like this, but since you have, don’t be skeptical about a plugin or theme being the source of the problem. 🙂

    Thread Starter briancbeers

    (@briancbeers)

    9 years ago

    I followed through on disabling the theme and using the default theme.
    I went in and did this before I ran the update.
    I was on the twentysixteen theme, and the update ran, but then it broke on the about page

    http://domain.name/wp-admin/about.php?updated

    The problem is that line 384 is trying to create a new class, and that class doesn’t exist…But based on the code it actually does exist.

    I updated PHP to 7.0 from 5.4, but this evidently wasn’t the problem either.
    I got a more thorough error message:
    Stack trace:
    #0 /home1/username/domain/wp-includes/taxonomy.php(72): register_taxonomy(‘category’, ‘post’, Array)
    #1 /home1/username/domain/wp-config.php(312): create_initial_taxonomies()
    #2 /home1/username/domain/wp-load.php(37): require_once(‘/home1/username…’)
    #3 /home1/username/domain/wp-admin/admin.php(31): require_once(‘/home1/username…’)
    #4 /home1/username/domain/wp-admin/about.php(10): require_once(‘/home1/username…’)
    #5 {main}
    thrown in <b>/home1/username/domain/wp-includes/taxonomy.php

    So the issue is still unresolved.

    Moderator James Huff

    (@macmanx)

    9 years ago

    That’s really odd, if it were WP itself, one would think we’d have more than just this one report after almost 3 million installations: https://wordpress.org/download/counter/ 🙁

    Are you absolutely sure the above was on a fresh update of WordPress 4.8, with no core file modifications, no active plugins, and the Twenty Sixteen theme?

    Moderator James Huff

    (@macmanx)

    9 years ago

    Are you running any sort of caching system? If so, perhaps the error is simply cached.

    After you update with clean unmodified core files, with all plugins deactivated while using the Twenty Sixteen theme, try flushing any caching plugins you might be running (consult their documentation for how to do this if you don’t have Dashboard access), as well as server and/or browser caches. Not just your browser, but any op cache or content network cache as well such as Cloudflare.

    Additionally, managed hosting often has special caches. If your host has a “Purge Varnish” or “Flush Memcache” tool, try that. You can ask your provider to flush memcache and Varnish for you if necessary.

Viewing 6 replies - 1 through 6 (of 6 total)

The topic ‘Fatal error: Class WP_Taxonomy not found in taxonomy.php line 384’ is closed to new replies.