Title: Cannot activate plugin
Last modified: August 22, 2016

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# Cannot activate plugin

 *  Resolved [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/)
 * Installation is ok but i cannot activate plugin:
 * Plugin could not be activated because it triggered a fatal error.
 * Fatal error: Call to undefined method Composer\Autoload\ClassLoader::set() in/***/***/
   public_html/wp-content/plugins/wp-statistics/vendor/composer/autoload_real.php
   on line 31
 * Any ideas?
 * [https://wordpress.org/plugins/wp-statistics/](https://wordpress.org/plugins/wp-statistics/)

Viewing 11 replies - 1 through 11 (of 11 total)

 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210224)
 * This is usually due to something missing from the install check the contents 
   of wp-statistics\vendor.
 * You can also try deleting and re-installing.
 *  Thread Starter [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210264)
 * tried that several times,… tried to instal from plugin manager and ftp,.. same
   thing
 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210280)
 * Check to make sure wp-statistics\vendor\composer contains the following 5 files:
 *     ```
       autoload_classmap.php	      147
       autoload_namespaces.php       491
       autoload_real.php           1,227
       ClassLoader.php             6,927
       installed.json              8,192
       ```
   
 *  Thread Starter [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210283)
 * hmm,. all are here
 * [http://www.serdarevic.net/screens/2014-08-20_15-17-25.png](http://www.serdarevic.net/screens/2014-08-20_15-17-25.png)
 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210294)
 * Perhaps another plugin has already defined the class without the set function,
   can you disable any other plugins your using and try it?
 *  Thread Starter [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210296)
 * this is the list of plugins i have,.. can you maybe suggest what to disable?
 * [http://www.serdarevic.net/screens/2014-08-20_15-56-05.png](http://www.serdarevic.net/screens/2014-08-20_15-56-05.png)
 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210298)
 * I’d suggest any that contains a vendor directory
 *  Thread Starter [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210301)
 * got it with first shot!!!
 * devmx-teamspeak3-webviewer
 * was causing this. let me see if i can find new TS plugin now…
 * Ill update!
 * Thanks!
 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210308)
 * Looks like that plugin hasn’t been updated for a while, probably has an older
   version of the autoloader bundled with it.
 *  Thread Starter [akyboy](https://wordpress.org/support/users/akyboy/)
 * (@akyboy)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210310)
 * prolly,
    hm,.. so i tested all, and looks like that your widget is not displaying
   what i need.
 * Id like to have list of last (ex.) 15 members visited. With visit date etc.
 * Do you have idea if something like that exist at all?
 *  Plugin Contributor [Greg Ross](https://wordpress.org/support/users/gregross/)
 * (@gregross)
 * [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210332)
 * I’m not familiar with a plugin that does that, but I’m sure there must be one
   in the plugin directory somewhere.

Viewing 11 replies - 1 through 11 (of 11 total)

The topic ‘Cannot activate plugin’ is closed to new replies.

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 * 11 replies
 * 2 participants
 * Last reply from: [Greg Ross](https://wordpress.org/support/users/gregross/)
 * Last activity: [11 years, 8 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-15/#post-5210332)
 * Status: resolved