ACCESS DENIED exception when opening a file in IIS virtual directory from aspx page.

Hi all,
I am trying to open a file from aspx page using java script. I am using window.open("file:////c:\\inetpub\wwwroor\MyFiles\mydoc.xps") in my java script to open the xps document. At this line of code, the debugger is throwing ACCESS DENIED exception. Am I missing some thing here? I am running IIS 5.1 and I gave IIS process account and ASPNET Account full control n the MYFILES folder.

Thanks in advance....
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