Title: An error occurred while using the plugin
Last modified: April 8, 2023

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# An error occurred while using the plugin

 *  [yoshi2023](https://wordpress.org/support/users/yoshi2023/)
 * (@yoshi2023)
 * [3 years, 2 months ago](https://wordpress.org/support/topic/an-error-occurred-while-using-the-plugin-2/)
 *     ```wp-block-code
       I use Salon Booking System-free.
   
       It worked fine at first and I didn’t even add any plugins. When I was working on it, I suddenly got an error. The error is below.
   
       Click Update Settings on the settings screen“This site has encountered a serious error.”occurred. It will return when you reload. settings are reflected.to the serverUncaught Error: Call to a member function add_cap() on null in /home/bij-marketing/www/pb-doc/wp-content/plugins/salon-booking-system/src/SLN/UserRole/SalonStaff.php:113Stack trace:
   
       0 /home/bij-marketing/www/pb-doc/wp-content/plugins/salon-booking-system/src/SLN/Admin/SettingTabs/GeneralTab.php(187): SLN_UserRole_SalonStaff::addCapabilities()
   
       1 /home/bij-marketing/www/pb-doc/wp-content/plugins/salon-booking-system/src/SLN/Admin/SettingTabs/AbstractTab.php(61): SLN_Admin_SettingTabs_GeneralTab->postProcess()
   
       2 /home/bij-marketing/www/pb-doc/wp-content/plugins/salon-booking-system/src/SLN/Admin/SettingTabs/AbstractTab.php(23): SLN_Admin_SettingTabs_AbstractTab->process()
   
       3 /home/bij-marketing/www/pb-doc/wp-content/plugins/salon-booking-system/src/SLN/Admin/Settings.php(53): SLN_Admin_SettingTabs_AbstractTab->__construct()
   
       4 /home/bij-marketing/www/pb-doc/wp-includes/class-wp-hook.php(308): SLN_Admin_Settings->show()
   
       5 /home/bij-marketing/www/pb-doc/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filte
   
       error message.WordPress is the latest version.Plugins are up to date.
   
       Is there any solution?
   
       The site is working without any problems, and there are no other management screens.Due to an error in the management screen, the link cannot be pasted.Does anyone have a similar phenomenon?
   
       I would be happy if you could teach me.
       ```
   

Viewing 1 replies (of 1 total)

 *  Plugin Author [Dimitri Grassi](https://wordpress.org/support/users/wordpresschef/)
 * (@wordpresschef)
 * [3 years, 1 month ago](https://wordpress.org/support/topic/an-error-occurred-while-using-the-plugin-2/#post-16660878)
 * Hi,
 * did you follow this guide:
 * [https://salonbookingsystem.helpscoutdocs.com/article/94-how-to-debug-issues](https://salonbookingsystem.helpscoutdocs.com/article/94-how-to-debug-issues)

Viewing 1 replies (of 1 total)

The topic ‘An error occurred while using the plugin’ is closed to new replies.

 * ![](https://ps.w.org/salon-booking-system/assets/icon-256x256.gif?rev=3214950)
 * [Salon Booking System - Free Version](https://wordpress.org/plugins/salon-booking-system/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/salon-booking-system/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/salon-booking-system/)
 * [Active Topics](https://wordpress.org/support/plugin/salon-booking-system/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/salon-booking-system/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/salon-booking-system/reviews/)

 * 1 reply
 * 2 participants
 * Last reply from: [Dimitri Grassi](https://wordpress.org/support/users/wordpresschef/)
 * Last activity: [3 years, 1 month ago](https://wordpress.org/support/topic/an-error-occurred-while-using-the-plugin-2/#post-16660878)
 * Status: not resolved