IIS7 Response.OutputStream does not work in IE7

Hi ,
    I am facing below issue as mentioned by "kent" in another forum
" Hi all.
 
So here is my problem. The application is hosted in Windows Server 2008 with IIS7.
 
I have a button  that calls a new webpage (asp.net page, ext .aspx) that contains
Response.OutputStream.Write(blahblahblah) which then should prompt a download box to allow user to save an image.
 
Now the page basically creates a stream and then is supposed to output the stream to the user using
Response.Outputstream.Write.
 
Then the user is supposed to be prompted to open or save the document.  This works fine in Firefox but it does not
work with IE7 or 8
 
Also this exact same code works with IIS6 on a Windows 2003 server.
 
So the only differences is the IIS6 and Windows 2003 Server to IIS7 and Windows ...