Fatal error: Uncaught Error: Cannot use object of type WP_Error as array in D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\src\Services\IisCompatService.php:19 Stack trace: #0 D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\src\Services\ServiceInstaller.php(25): Trs\Services\IisCompatService->install() #1 D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\src\Loader.php(119): Trs\Services\ServiceInstaller->installIfReady(Object(Trs\Services\IisCompatService)) #2 D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\src\Loader.php(22): Trs\Loader->installServices() #3 D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\bootstrap.php(14): Trs\Loader->bootstrap() #4 D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\bootstrap.php(15): {closure}() #5 D in D:\appdata\IIS\vhosts\zephyrusrecords.be\httpdocs\wp-content\plugins\wc-tree-table-rate-shipping\src\Services\IisCompatService.php on line 19