Title: fatal error
Last modified: May 31, 2019

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# fatal error

 *  Resolved [tangorosso](https://wordpress.org/support/users/tangorosso/)
 * (@tangorosso)
 * [7 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-3221/)
 * I have charged on my web site the plugin but when I try to activate I have this
   error:
 * Fatal error: Call to undefined function wp_doing_ajax() in /web/htdocs/www.lightofromebb.
   com/home/wp-content/plugins/vikbooking/vikbooking.php on line 393
 * The version is the free version that I want to try to evaluate the pro.
 * Greetings
 * The page I need help with: _[[log in](https://login.wordpress.org/?redirect_to=https%3A%2F%2Fwordpress.org%2Fsupport%2Ftopic%2Ffatal-error-3221%2F%3Foutput_format%3Dmd&locale=en_US)
   to see the link]_

Viewing 1 replies (of 1 total)

 *  Plugin Author [e4jvikwp](https://wordpress.org/support/users/e4jvikwp/)
 * (@e4jvikwp)
 * [7 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-3221/#post-11595041)
 * Hello,
 * The function wp_doing_ajax() is a native function of WordPress introduced in 
   the version 4.7 of the framework as you can see from the link below:
 * [https://developer.wordpress.org/reference/functions/wp_doing_ajax/](https://developer.wordpress.org/reference/functions/wp_doing_ajax/)
 * We state that the minimum WordPress version required for using Vik Booking is
   the 4.7, so I guess you are using an outdated version of WordPress.
 * The only solution to resolve that error is to simply upgrade to a newer version
   of WordPress. Then everything should work fine.

Viewing 1 replies (of 1 total)

The topic ‘fatal error’ is closed to new replies.

 * ![](https://ps.w.org/vikbooking/assets/icon-256x256.png?rev=1855707)
 * [VikBooking Hotel Booking Engine & PMS](https://wordpress.org/plugins/vikbooking/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/vikbooking/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/vikbooking/)
 * [Active Topics](https://wordpress.org/support/plugin/vikbooking/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/vikbooking/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/vikbooking/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [e4jvikwp](https://wordpress.org/support/users/e4jvikwp/)
 * Last activity: [7 years, 3 months ago](https://wordpress.org/support/topic/fatal-error-3221/#post-11595041)
 * Status: resolved