Title: Cannot Activate Plugin Last modified: December 1, 2019 --- # Cannot Activate Plugin * Resolved [Edna Houston](https://wordpress.org/support/users/ediehouston/) * (@ediehouston) * [6 years, 6 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-60/) * Cannot activate due to fatal error: * Version 3.5.2.1 On WordPress 5.3 * Fatal error: Uncaught Error: Class ‘FS_Admin_Notices’ not found in path/plugins/ wp-security-audit-log/classes/Settings.php:1559 Stack trace: #0 path/plugins/ wp-security-audit-log/wp-security-audit-log.php(1248): WSAL_Settings->set_mainwp_child_stealth_mode()# 1 path/wp-includes/class-wp-hook.php(288): WpSecurityAuditLog->Install(”) #2 path/wp-includes/class-wp-hook.php(312): WP_Hook->apply_filters(”, Array) #3 path/wp-includes/plugin.php(478): WP_Hook->do_action(Array) #4 path/wp-admin/ plugins.php(177): do_action(‘activate_wp-sec…’) #5 {main} thrown in path/plugins/ wp-security-audit-log/classes/Settings.php on line 1559 Viewing 3 replies - 1 through 3 (of 3 total) * Plugin Support [robertabela](https://wordpress.org/support/users/robert681/) * (@robert681) * [6 years, 6 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-60/#post-12196263) * Sorry to see you’re encountering such a problem [@ediehouston](https://wordpress.org/support/users/ediehouston/) * Is this a new install or an update? * Also, is the site on which you are installing the plugin part of a MainWP network? Is the MainWP Child site plugin installed as well on the same site? * Looking forward to hearing from you. * Thread Starter [Edna Houston](https://wordpress.org/support/users/ediehouston/) * (@ediehouston) * [6 years, 6 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-60/#post-12198616) * This is a new install of this addon and it is part of a MainWP Network. The MainWP Child plugin is installed and activated with no problem. This addon installed and activated on another site in the network with no problem. * [williampatton](https://wordpress.org/support/users/williampatton/) * (@williampatton) * [6 years, 6 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-60/#post-12201493) * Hey [@ediehouston](https://wordpress.org/support/users/ediehouston/), * Sorry your having a problem here. I am looking into this issue and have not been able to recreate the exact same error message you have got but I am continuing to test on my side. Could you let me know a bit about your setup and the network your running things on? If you know the PHP version that would be good but if you don’t know it no problem. * Do you know what kind of network it is between: subdomain (site.domain.com), a subsite (domain.com/site) or using domain mapping like (domain1.com and domain2. com)? * Also if at all possible could you try to upload a fresh copy of the files over the top of the existing ones with something like ftp? * If you need any guidance for finding out anything here or how to use an ftp client let me know and I will be happy to help walk you through that. Viewing 3 replies - 1 through 3 (of 3 total) The topic ‘Cannot Activate Plugin’ is closed to new replies. * ![](https://ps.w.org/wp-security-audit-log/assets/icon-256x256.png?rev=2961534) * [WP Activity Log](https://wordpress.org/plugins/wp-security-audit-log/) * [Frequently Asked Questions](https://wordpress.org/plugins/wp-security-audit-log/#faq) * [Support Threads](https://wordpress.org/support/plugin/wp-security-audit-log/) * [Active Topics](https://wordpress.org/support/plugin/wp-security-audit-log/active/) * [Unresolved Topics](https://wordpress.org/support/plugin/wp-security-audit-log/unresolved/) * [Reviews](https://wordpress.org/support/plugin/wp-security-audit-log/reviews/) ## Tags * [fatal error](https://wordpress.org/support/topic-tag/fatal-error/) * 3 replies * 3 participants * Last reply from: [williampatton](https://wordpress.org/support/users/williampatton/) * Last activity: [6 years, 6 months ago](https://wordpress.org/support/topic/cannot-activate-plugin-60/#post-12201493) * Status: resolved