Hash fragments with forward-slash throwing 403 errors with AJAX requests in IE

I have a URL similar to: http://www.example.com/#!/test/

And an AJAX request that is handled when the hash fragment is /test/. The AJAX request is fine except in IE, where it throws a 403 error. It works fine in all other browsers.

Now, if I change the URL to: http://www.example.com/#!test/

It works just fine. I can't change my current hash fragment URL structure. Any solutions/suggestions?

Use a network debugger (e.g. www.fiddler2.com) and determine what the difference in the HTTP request is that results in the server sending back a different response. My guess is that the way that you're getting the data out of the hash results in sending a different query to the server between browsers (e.g. includes "#" or lacks "#") and that causes the server to return the 403 to IE.