try a image link
echo "<img src=\"/folder1/folder2/page.asp?string=".$string." \" width=\"1\" height=\"1">"
you can hide the image link of screen
in php i use this to link images via another php script from html page so should work for asp but never tried
the php script is run but not shown in browser
i send back image link from php script with header("Location: link/image.jpg");
so you could also link back with a response ok image or a responce failed image if you wish