Support » Plugin: Multisite Language Switcher » Installed but "fatal error" .. need multisite prevents activation

  • Resolved pimlico35


    Hi, I recently re-installed this plugin (previously although “activated” wouldnt show on site) so I did a fresh install via cpanel.

    Cannot activate the plugin as it says fatal error and need a multisite to run plugin ??

    I can follow clear instructions to change files in cpanel and wordpress – however nervously! Just want 2 extra languages available in header for users to switch to. Prefer a translation of main site.


Viewing 8 replies - 1 through 8 (of 8 total)
  • Plugin Author Dennis Ploetner


    I’m sorry but you need a multisite for this plugin.

    Read on here:

    I checked your installation guide and the answer is not here:
    1- Activated plugin: Fatal error: Call to undefined function is_user_logged_in() in /home/content/20/11289920/html/wp-content/plugins/user-language-switch/user-language-switch.php on line 117

    2- I deleted the plugin through ftp, now the front-end and back-end are working again

    3- Only when i try to click on the plugin section it still gives “Fatal Error”, so what files i need to remove in order to get the “install plugin” section to work again?

    Please advice


    Plugin Author Dennis Ploetner


    This has nothing to do with the Multisite Language Switcher. And please open your a new thread when you have an issue.

    Please look at the path


    The function is_user_logged_in is a WordPress standard function.

    When a plugin not works you can indeed remove the folder where the plugin is stored and that’s it.


    Hi Dennis,

    Not sure if i understand you, i’m not a coder.

    The only thing i know is that the problem occured right after installing your plugin, i mean 2 seconds after. So might your plugin be causing a conflict with another plugin? How do i go on solving this?

    I already removed your plugin from the folder, first i was getting the error above for whole the site…


    Plugin Author Dennis Ploetner


    OK, lets try to find out what’s going on there:

    Try first to deactivate the plugin which reports the error: the User Language Switch… if there are still problems: The Multisite Language Switcher is normally installed in


    if you have problems with this plugin, you should remove this folder.

    Le me know what’s going on.

    Hey Dennis, thanks for your help.

    1. I did delete the Multisite Language Switcher immediately after the error occured.

    2. I cannot deactivate any plugins since when i click on the plugins section i get the “Fatal Error….etc.”

    Is there a way to manually deactivate the User Language Switch plugin ?

    (…all of these steps i also wrote in the posts above a few minutes ago…)

    Ok the plugin Multisite Language Switcher wasn’t removed properly!

    Now it’s removed and everything is working fine again.

    Thanks again!

    Plugin Author Dennis Ploetner


    The Multisite Language Switcher works fine with WP Native Dashbord if you look for an alternative solution.

Viewing 8 replies - 1 through 8 (of 8 total)
  • The topic ‘Installed but "fatal error" .. need multisite prevents activation’ is closed to new replies.