hey!
i did - with no success

, but i solved it another way.
i put this code into the includes/config.php file: define('DISABLE_HOOKS', true); (i think it disables all plugins and add-ons) and so i got access to the "plugin management" and i could uninstall the plugin.
after that i removed define('DISABLE_HOOKS', true); from the includes/config.php and my forum was fine again

.
thanks anyway

.