Title: Fatal Error Cause
Last modified: August 30, 2016

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# Fatal Error Cause

 *  Resolved [Amito](https://wordpress.org/support/users/andrewsegawa/)
 * (@andrewsegawa)
 * [10 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-cause/)
 * Hello
 * When i activate this plugin i get a error
 * “Fatal error: Unknown: Cannot use output buffering in output buffering display
   handlers in Unknown on line 0”
 * Activating it makes the website fine.
 * Is there any solution
 * [https://wordpress.org/plugins/autoptimize/](https://wordpress.org/plugins/autoptimize/)

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

 *  Plugin Author [Frank Goossens](https://wordpress.org/support/users/futtta/)
 * (@futtta)
 * [10 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-cause/#post-6366600)
 * that typically is a conflict with another plugin that is doing output buffering
   as well (and probably the wrong way). if you want to use AO, you’ll have to disable
   other plugins selectively to identify where the conflict is. if you have that,
   I’ll be happy to have a look to see if this is fixable.
 * hope this helps,
    frank
 *  Thread Starter [Amito](https://wordpress.org/support/users/andrewsegawa/)
 * (@andrewsegawa)
 * [10 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-cause/#post-6366730)
 * Yes, am using W3 Total Cache
 * Cant these two plugins be used together?
 *  Plugin Author [Frank Goossens](https://wordpress.org/support/users/futtta/)
 * (@futtta)
 * [10 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-cause/#post-6366734)
 * You’ll have to disable all minification in W3TC for this will work; having 2 
   plugins do minification will almost always cause ugliness.
 * frank

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

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

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 * 3 replies
 * 2 participants
 * Last reply from: [Frank Goossens](https://wordpress.org/support/users/futtta/)
 * Last activity: [10 years, 10 months ago](https://wordpress.org/support/topic/fatal-error-cause/#post-6366734)
 * Status: resolved