IIS 7 HTTP Redirection to Remove Trailing Slash

Question

We start the server with IIS 7, and I configured 301 HTTP Redirect for the IIS site, forwarding URL:

http://www.websitename.com/deliveries/

When IIS is redirected to this URL, it removes the trailing slash, and therefore the web server processing the URL "http://www.websitename.com/deliveries" cannot load the correct content because it is waiting for the final slash (I do not have control over this web server or site). Adding index.php to the URL works, but I would prefer it to work with the correct URL!

Any ideas?