Problem (mysql)

Hello

I have problem with free version. Whenever i add group and try to edit it, I get message:

Fatal error: Uncaught Error: [] operator not supported for strings in /home/korosk25/public_html/wp-content/plugins/adrotate/dashboard/publisher/groups-edit.php:32 Stack trace: #0 /home/korosk25/public_html/wp-content/plugins/adrotate/adrotate.php(324): include() #1 /home/korosk25/public_html/wp-includes/class-wp-hook.php(298): adrotate_manage_group(”) #2 /home/korosk25/public_html/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(”, Array) #3 /home/korosk25/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #4 /home/korosk25/public_html/wp-admin/admin.php(222): do_action(‘adrotate_page_a…’) #5 {main} thrown in /home/korosk25/public_html/wp-content/plugins/adrotate/dashboard/publisher/groups-edit.php on line 32

And when I want to edit and save ads, i get this msg:

Fatal error: Uncaught Error: [] operator not supported for strings in /home/korosk25/public_html/wp-content/plugins/adrotate/adrotate-manage-publisher.php:139 Stack trace: #0 /home/korosk25/public_html/wp-includes/class-wp-hook.php(298): adrotate_insert_input(”) #1 /home/korosk25/public_html/wp-includes/class-wp-hook.php(323): WP_Hook->apply_filters(NULL, Array) #2 /home/korosk25/public_html/wp-includes/plugin.php(453): WP_Hook->do_action(Array) #3 /home/korosk25/public_html/wp-settings.php(449): do_action(‘init’) #4 /home/korosk25/public_html/wp-config.php(93): require_once(‘/home/korosk25/…’) #5 /home/korosk25/public_html/wp-load.php(37): require_once(‘/home/korosk25/…’) #6 /home/korosk25/public_html/wp-admin/admin.php(31): require_once(‘/home/korosk25/…’) #7 {main} thrown in /home/korosk25/public_html/wp-content/plugins/adrotate/adrotate-manage-publisher.php on line 139