Title: Fatal error: Call to undefined function get_plugin_data()
Last modified: March 1, 2017

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# Fatal error: Call to undefined function get_plugin_data()

 *  Resolved [cronwerk](https://wordpress.org/support/users/cronwerk/)
 * (@cronwerk)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/)
 * I tried again to use the plugin in my multisite with 2 sites in sub-directories(
   site and site/en/) with 2 activated plugins: Easy SMTP and Blue Admin. I need
   these 2 plugins and won’t abandon them.
    In your installation instruction you
   wrote: “Upload plugin-name.php to the /wp-content/plugins/ directory” Did you
   really mean the file plugin-name.php? But there is no such file. Is it user-upgrade-
   capability.php? But then what for are all other files?
 * So I uploaded the whole plugin folder /user-upgrade-capability/ to /wp-content/
   plugins/. Was it wrong?
    I activated the plugin for network and was immediately
   redirected to the white screen with message: “Fatal error: Call to undefined 
   function get_plugin_data() in /var/www/html/test-2/wp-content/plugins/user-upgrade-
   capability/user-upgrade-capability.php on line 311” I couldn’t enter the site
   anymore.
 * Then I literally fulfilled your instruction and uploaded only the file user-upgrade-
   capability.php to /wp-content/plugins/. Of course I’ve got a white screen with
   error message.
 * I didn’t try to activate the plugin for each site of multisite because the 1-
   st issue revealed it’s dangerous features.

Viewing 7 replies - 1 through 7 (of 7 total)

 *  Plugin Author [Justin Fletcher](https://wordpress.org/support/users/justinticktock/)
 * (@justinticktock)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8860541)
 * for the “Upload plugin-name.php to the /wp-content/plugins/ directory”
    you are
   right I’ll update that instruction its generic and not helpful, the easiest way
   in install is to pull the plugin from the WordPress plugin repository
 * the final state should be
 * ../wp-content/plugins/user-upgrade-capability/ <files in here>
 * can you install it through the WordPress plugin repository “add plugins” automatic
   installer. So follow these steps..
    1) remove/delete the plugin folder you created
   manually (e.g. ../wp-content/plugins/**user-upgrade-capability**/ 2) Go to site
   dashboard ‘My Sites’ > ‘Network Admin’ > ‘Plugins’ 3) Click on the ‘Add New’ 
   button 4) search for ‘User upgrade capability’ and install 5) Network Activate
   the plugin
 * let me know if you get the same results.
 * when you say “_I didn’t try to activate the plugin for each site of multisite
   because the 1-st issue revealed it’s dangerous features._”
    the plugin is a network
   wide activation you don’t need to do this per site, once its active it will be
   active on each of the network sites. You simple start to use it on a site instance
   by configuring a reference site and away you go.
 *  Plugin Author [Justin Fletcher](https://wordpress.org/support/users/justinticktock/)
 * (@justinticktock)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8860574)
 * FYI I’ve updated the install notes section..
    [https://wordpress.org/plugins/user-upgrade-capability/installation/](https://wordpress.org/plugins/user-upgrade-capability/installation/)
 *  Thread Starter [cronwerk](https://wordpress.org/support/users/cronwerk/)
 * (@cronwerk)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8861467)
 * When plugins are installed through dashboard sites are 2-3 times slower than 
   after manually unzipped folder uploading.
    I don’t know why but it is my experimental
   fact. So installation through dashboard is unacceptable for me.
 *  Plugin Author [Justin Fletcher](https://wordpress.org/support/users/justinticktock/)
 * (@justinticktock)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8861983)
 * that doesn’t sound right, the site should not behave any different with either
   the auto/dashboard install or a manual upload of files. Both end up with php 
   files and there is no difference.
 * Have a look at separately re-installing WordPress again and seeing if the same
   behavior occurs on a fresh install.
 * a good resource for de-bugging is by scribu
    [https://github.com/scribu/wp-posts-to-posts/wiki/Troubleshooting](https://github.com/scribu/wp-posts-to-posts/wiki/Troubleshooting)
    -  This reply was modified 9 years, 1 month ago by [Justin Fletcher](https://wordpress.org/support/users/justinticktock/).
 *  Thread Starter [cronwerk](https://wordpress.org/support/users/cronwerk/)
 * (@cronwerk)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8862143)
 * I installed WP above 100 times for myself and for my clients. And each time when
   I manually copied plugins in /wp-conten/ the DB was nearly 2 times larger (for
   example 1 Mb vs. 605 kb) but site worked 2-4 times faster than under dashboard
   installing (for example 0,75 c vs. 2,5 – 3,4 c for page loading).
    Never mind
   that “site SHOULD NOT behave any different”. It’s important that it really DOES.
   While installing plugins WP core makes changes in meta data, in DB. The method
   of installing influences on result.
    -  This reply was modified 9 years, 1 month ago by [cronwerk](https://wordpress.org/support/users/cronwerk/).
    -  This reply was modified 9 years, 1 month ago by [cronwerk](https://wordpress.org/support/users/cronwerk/).
 *  Plugin Author [Justin Fletcher](https://wordpress.org/support/users/justinticktock/)
 * (@justinticktock)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8862536)
 * I’ll have to look at the database with both installations manual/auto at somepoint.
   
   Either way a manual install of the plug is fine if you prefer.
 * so that would be here ..
    ../wp-content/plugins/user-upgrade-capability\readme.
   txt ../wp-content/plugins/user-upgrade-capability\uninstall.php ../wp-content/
   plugins/user-upgrade-capability\user-upgrade-capability.php ../wp-content/plugins/
   user-upgrade-capability\includes\class-tabbed-settings.php ../wp-content/plugins/
   user-upgrade-capability\includes\class-tgm-plugin-activation.php ../wp-content/
   plugins/user-upgrade-capability\includes\class-user-upgrade-capability-network-
   info.php ../wp-content/plugins/user-upgrade-capability\includes\plugin-install.
   php ../wp-content/plugins/user-upgrade-capability\includes\settings-general.php../
   wp-content/plugins/user-upgrade-capability\includes\settings-upgrade-caps.php../
   wp-content/plugins/user-upgrade-capability\includes\settings-upgrade-roles.php
 *  Thread Starter [cronwerk](https://wordpress.org/support/users/cronwerk/)
 * (@cronwerk)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8862723)
 * Thank you for consultation.
    Best regards.

Viewing 7 replies - 1 through 7 (of 7 total)

The topic ‘Fatal error: Call to undefined function get_plugin_data()’ is closed 
to new replies.

 * ![](https://ps.w.org/user-upgrade-capability/assets/icon.svg?rev=980608)
 * [User Upgrade Capability](https://wordpress.org/plugins/user-upgrade-capability/)
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 * 7 replies
 * 2 participants
 * Last reply from: [cronwerk](https://wordpress.org/support/users/cronwerk/)
 * Last activity: [9 years, 1 month ago](https://wordpress.org/support/topic/fatal-error-call-to-undefined-function-get_plugin_data/#post-8862723)
 * Status: resolved