Plugin install, fatal error, database

Hi, I have a problem with the activation of the plugin. I can not activate it, I get an error message. On a fresh WordPress installation I can activate the plugin without any problems but I would like to try the plugin on my existing site and not set up everything from scratch. Before Plugins Install: https://dev.not-idea.de/wp-content/uploads/1.jpg After Plugin Install: https://dev.not-idea.de/wp-content/uploads/2.jpg Warning: Undefined property: WP_Post_Type::$custom_rewrite in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 181 Warning: Undefined property: WP_Post_Type::$custom_query_var in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 183 Warning: Undefined property: WP_Post_Type::$custom_rewrite in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 181 Warning: Undefined property: WP_Post_Type::$custom_query_var in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 183 Warning: Undefined property: WP_Post_Type::$custom_rewrite in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 181 Warning: Undefined property: WP_Post_Type::$custom_query_var in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 183 Warning: Undefined property: WP_Post_Type::$custom_rewrite in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 181 Warning: Undefined property: WP_Post_Type::$custom_query_var in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 183 Warning: Undefined property: WP_Post_Type::$custom_rewrite in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 181 Warning: Undefined property: WP_Post_Type::$custom_query_var in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 183 Warning: Undefined array key 0 in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 227 Fatal error: Uncaught Error: Call to a member function getId() on null in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php:229 Stack trace: #0 /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php(106): ACPT_Lite\Includes\ACPT_Lite_DB::createNativeTaxonomies() #1 /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/advanced-custom-post-type-lite.php(82): ACPT_Lite\Includes\ACPT_Lite_DB::sync() #2 /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/advanced-custom-post-type-lite.php(92): ACPT_Lite::checkForPluginUpgrades() #3 /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-admin/includes/plugin.php(2288): include_once('/var/www/vhosts...') #4 /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-admin/plugins.php(192): plugin_sandbox_scrape('acpt-lite/advan...') #5 {main} thrown in /var/www/vhosts/hosting134183.a2e34.netcup.net/httpdocs/not-idea/dev/wp-content/plugins/acpt-lite/src/Includes/ACPT_Lite_DB.php on line 229 Best Regards Andibo Hi Andibo, and thank you so much for reporting this issue. The errors seem to be in the sync process. I don’t know why this happens but I can introduce a conditional statement in this part of the code to avoid the error. Anyway, you can reach me at info@acpt.io in order to provide me more details to replicate the bug on my end. Thank you in advance! Mauro The errors shown refer to a PHP8 incompatibility, there was a breaking change in call_user_func_array function. At the present time (2022-04-26) the plugin is not tested yet on PHP8 . I’ll try to release the patch as soon as possible, then the topic will be updated and closed 🙂 Thanks a lot for your time, with your help the plugin works now on my website! Best Regards Andi