Upgrade to 2.7 creates problem with index.php file

I recently updated a client to 2.7 and now when you go to http://www.granolagourmet.com/index.php it instead redirects to http://www.granolagourmet.com/index.html and I need that file to be there for the homepage which is static. It was working fine prior to this and now it doesn’t. What’s the fix?