IIS 7.5 web server doesn't display the response page from a cgi script

We have an old cgi script (.exe) that is being migrated from an old iis server running on windows xp to iis 7.5 on win 7.  Everything has been working fine for years on the old machine.

This script pulls data off a web form and saves it to a local file, and then is supposed to load a static html response page.

The first part works fine, but the second does not.

In Firefox, we get a message that the connection was reset while the page was loading.

In IE, the error message is "This page cannot be displayed"

We can access the htm page just fine via either browser, but it just doesn't load when the .exe tries to do it.  

Would really appreciate any thoughts!  We do not have access to the source code of the script as it was provided by a software vendor.