Hi Dam,
I did (before I posted and re-tried now again). Result: Same error message. Debug shows:
ERROR 0 - OSModelList::_buildQueryColumns(): Argument #1 ($query) must be of type JDatabaseQuery, Joomla\Database\Mysqli\MysqliQuery given, called in /[...]/administrator/components/com_edocman/libraries/rad/model/list.php on line 132 in /[...]/administrator/components/com_edocman/libraries/rad/model/list.php:194
and:
() JROOT/administrator/components/com_edocman/libraries/rad/model/list.php:194
2 OSModelList->_buildQueryColumns() JROOT/administrator/components/com_edocman/libraries/rad/model/list.php:132
3 OSModelList->getData() JROOT/components/com_edocman/model/categories.php:46
4 EDocmanModelCategories->getData() JROOT/components/com_edocman/view/categories/html.php:25
5 EDocmanViewCategoriesHtml->display() JROOT/administrator/components/com_edocman/libraries/rad/controller/controller.php:368
6 OSController->display() JROOT/components/com_edocman/controller/controller.php:56
7 EDocmanController->display() JROOT/administrator/components/com_edocman/libraries/rad/controller/controller.php:306
8 OSController->execute() JROOT/components/com_edocman/edocman.php:42
9 require_once() JROOT/libraries/src/Dispatcher/LegacyComponentDispatcher.php:71
10 Joomla\CMS\Dispatcher\LegacyComponentDispatcher::Joomla\CMS\Dispatcher\{closure}() JROOT/libraries/src/Dispatcher/LegacyComponentDispatcher.php:73
11 Joomla\CMS\Dispatcher\LegacyComponentDispatcher->dispatch() JROOT/libraries/src/Component/ComponentHelper.php:361
12 Joomla\CMS\Component\ComponentHelper::renderComponent() JROOT/libraries/src/Application/SiteApplication.php:218
13 Joomla\CMS\Application\SiteApplication->dispatch() JROOT/libraries/src/Application/SiteApplication.php:261
14 Joomla\CMS\Application\SiteApplication->doExecute() JROOT/libraries/src/Application/CMSApplication.php:306
15 Joomla\CMS\Application\CMSApplication->execute() JROOT/includes/app.php:58
16 require_once() JROOT/index.php:32
Hope this helps you to help me
Thanks
Thorsten