Title: Please help – Error
Last modified: April 17, 2017

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# Please help – Error

 *  [filmtopp](https://wordpress.org/support/users/filmtopp/)
 * (@filmtopp)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/please-help-error/)
 * Hi!
    I really, really like this plugin and I consider to purchase the premium
   version. But in the last couple of days the plugin has been causing problem on
   my site.
 * I get a 500 error message and in the error log I could see (on several occasions)
   that it was your plugin that caused it.
 * [17-Apr-2017 08:08:24 UTC] PHP Fatal error: Call to undefined function is_user_logged_in()
   in /home/filmtopp/public_html/wp-content/plugins/wp-fastest-cache/inc/cache.php
   on line 416
 * What to do about it?
    Please help.

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

 *  Plugin Author [Emre Vona](https://wordpress.org/support/users/emrevona/)
 * (@emrevona)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/please-help-error/#post-9036790)
 * is_user_logged_in() is a wp native function. if it does not work, you have another
   problem I guess.
 *  Thread Starter [filmtopp](https://wordpress.org/support/users/filmtopp/)
 * (@filmtopp)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/please-help-error/#post-9036793)
 * Thanks for your reply. I don’t really understand what it means though… could 
   you please explain?
 *  Plugin Author [Emre Vona](https://wordpress.org/support/users/emrevona/)
 * (@emrevona)
 * [9 years, 1 month ago](https://wordpress.org/support/topic/please-help-error/#post-9037960)
 * Please contact me via email: [http://www.wpfastestcache.com/contact-us/](http://www.wpfastestcache.com/contact-us/)

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

The topic ‘Please help – Error’ is closed to new replies.

 * ![](https://ps.w.org/wp-fastest-cache/assets/icon-256x256.png?rev=2064586)
 * [WP Fastest Cache - WordPress Cache Plugin](https://wordpress.org/plugins/wp-fastest-cache/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/wp-fastest-cache/#faq)
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 * [Active Topics](https://wordpress.org/support/plugin/wp-fastest-cache/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/wp-fastest-cache/unresolved/)
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## Tags

 * [cache](https://wordpress.org/support/topic-tag/cache/)
 * [PHP Fatal error](https://wordpress.org/support/topic-tag/php-fatal-error/)
 * [php-error](https://wordpress.org/support/topic-tag/php-error/)

 * 3 replies
 * 2 participants
 * Last reply from: [Emre Vona](https://wordpress.org/support/users/emrevona/)
 * Last activity: [9 years, 1 month ago](https://wordpress.org/support/topic/please-help-error/#post-9037960)
 * Status: not resolved