Does not work to put new products in the Home Page Slideshow

Sheep next error message:

Notice: Undefined index: sort_order in /customers/c/5/d/zeilshop.se/httpd.www/store/admin/model/design/banner.php on line 37Warning: Cannot modify header information - headers already sent by (output started at /customers/c/5/d/zeilshop.se/httpd.www/store/admin/index.php:80) in/customers/c/5/d/zeilshop.se/httpd.www/store/system/library/response.php on line 12

Does anyone know what this is about?

There was a temporary error. I try again and it worked.