Title: Error activating plugin
Last modified: August 31, 2016

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# Error activating plugin

 *  Resolved [cbelinsky](https://wordpress.org/support/users/cbelinsky/)
 * (@cbelinsky)
 * [10 years, 1 month ago](https://wordpress.org/support/topic/error-activating-plugin-23/)
 * I get the following error trying to activate WordFence:
    Plugin could not be 
   activated because it triggered a fatal error.
 * This is for version 6.1.2.
 * I tried installing an older version (5.3.12) and it installed and activated but
   then I got the white screen of death. Debugging gave me the following:
 * [14-Apr-2016 18:38:49] PHP Warning: require_once(lib/wordfenceConstants.php):
   failed to open stream: No such file or directory in E:\Inetpub\edutech\wp-content\
   plugins\wordfence\wordfence.php on line 23
    [14-Apr-2016 18:38:49] PHP Fatal 
   error: require_once(): Failed opening required ‘lib/wordfenceConstants.php’ (
   include_path=’.;C:\php\pear’) in E:\Inetpub\edutech\wp-content\plugins\wordfence\
   wordfence.php on line 23 [14-Apr-2016 18:38:49] PHP Warning: require_once(lib/
   wordfenceConstants.php): failed to open stream: No such file or directory in 
   E:\Inetpub\edutech\wp-content\plugins\wordfence\wordfence.php on line 23 [14-
   Apr-2016 18:38:49] PHP Fatal error: require_once(): Failed opening required ‘
   lib/wordfenceConstants.php’ (include_path=’.;C:\php\pear’) in E:\Inetpub\edutech\
   wp-content\plugins\wordfence\wordfence.php on line 23
 * The file wordfenceConstants.php exists in the right folder and has full access
   permissions.
 * Things I have tried (with no success):
    – disabling all other plugins – changing
   themes – increasing memory limit: define( ‘WP_MEMORY_LIMIT’, ‘256M’ ); – manually
   deleting the WordFence folder and downloading it directly – upgrading WordPress(
   the same things are happening in WP 4.4 and 4.5)
 * I have multiple other WordPress sites (not networked) successfully using WordFence.
 * thanks for your help,
    Charlie

Viewing 3 replies - 1 through 3 (of 3 total)

 *  Moderator [James Huff](https://wordpress.org/support/users/macmanx/)
 * (@macmanx)
 * [10 years, 1 month ago](https://wordpress.org/support/topic/error-activating-plugin-23/#post-7278334)
 * I recommend asking at [https://wordpress.org/support/plugin/wordfence#postform](https://wordpress.org/support/plugin/wordfence#postform)
   so the plugin’s developers and support community can help you with this.
 *  Thread Starter [cbelinsky](https://wordpress.org/support/users/cbelinsky/)
 * (@cbelinsky)
 * [10 years, 1 month ago](https://wordpress.org/support/topic/error-activating-plugin-23/#post-7278451)
 * Argh, my mistake, I meant to do that.
 * thanks,
    Charlie
 *  Moderator [James Huff](https://wordpress.org/support/users/macmanx/)
 * (@macmanx)
 * [10 years, 1 month ago](https://wordpress.org/support/topic/error-activating-plugin-23/#post-7278464)
 * You’re welcome!
 * [https://wordpress.org/support/topic/fatal-error-on-activation-98](https://wordpress.org/support/topic/fatal-error-on-activation-98)

Viewing 3 replies - 1 through 3 (of 3 total)

The topic ‘Error activating plugin’ is closed to new replies.

 * In: [Fixing WordPress](https://wordpress.org/support/forum/how-to-and-troubleshooting/)
 * 3 replies
 * 2 participants
 * Last reply from: [James Huff](https://wordpress.org/support/users/macmanx/)
 * Last activity: [10 years, 1 month ago](https://wordpress.org/support/topic/error-activating-plugin-23/#post-7278464)
 * Status: resolved

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