Title: Fatal Error
Last modified: August 22, 2016

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# Fatal Error

 *  [jwurster](https://wordpress.org/support/users/jwurster/)
 * (@jwurster)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-1541/)
 * I wanted to add a caching plugin to our site at [http://ourcommunitycup.com](http://ourcommunitycup.com)
   to speed up page loading, I tried several but all resulted in the following error
   when I went to activate them:
 * Fatal error: Class ‘C_NextGen_Settings’ not found in /home/commcup/public_html/
   wp-content/plugins/nextgen-gallery-optimizer/admin/assets/install/class-nggobasic-
   fancybox-installer-nextgen-v2.php on line 197
 * Since this error pointed to the NextGen Gallery Optimizer plugin, I thought I
   would deactivate it and see whether I could activate a caching plugin. I got 
   this error:
 * Fatal error: Call to undefined method C_Lightbox_Installer::uninstall_lightbox()
   in /home/commcup/public_html/wp-content/plugins/nextgen-gallery-optimizer/admin/
   assets/install/class-nggobasic-lightbox-installer-nextgen-v2.php on line 201
 * Any ideas how to resolve this?
 * Thank you, jim
 * [https://wordpress.org/plugins/nextgen-gallery/](https://wordpress.org/plugins/nextgen-gallery/)

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

 *  Plugin Contributor [photocrati](https://wordpress.org/support/users/photocrati/)
 * (@photocrati)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-1541/#post-5861137)
 * [@jwurster](https://wordpress.org/support/users/jwurster/) – Those are definitely
   related to the NextGEN Gallery Optimizer plugin … there apparently is a conflict
   with that third-party extension again. I would recommend contacting its author
   as he will be working on getting this sorted out.
 * Thanks!
 * – Cais.
 *  Thread Starter [jwurster](https://wordpress.org/support/users/jwurster/)
 * (@jwurster)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-1541/#post-5861143)
 * Thank you. I posted there.
 *  Plugin Contributor [photocrati](https://wordpress.org/support/users/photocrati/)
 * (@photocrati)
 * [11 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-1541/#post-5861145)
 * [@jwurster](https://wordpress.org/support/users/jwurster/) – Thanks!
 * – Cais.

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

The topic ‘Fatal Error’ is closed to new replies.

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## Tags

 * [caching](https://wordpress.org/support/topic-tag/caching/)
 * [gallery](https://wordpress.org/support/topic-tag/gallery/)
 * [nextgen](https://wordpress.org/support/topic-tag/nextgen/)

 * 3 replies
 * 2 participants
 * Last reply from: [photocrati](https://wordpress.org/support/users/photocrati/)
 * Last activity: [11 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-1541/#post-5861145)
 * Status: not a support question