Streaming a dynamically created (from ASP.NET ) xml file (using memorystream) to let the client application pick it up automatically...

Guys,

I have a client tool which runs and accepts files with "amt"
extensions.   All the "amt" files have been setup to open using my
client tool which works great when I double-click on the file in the
windows explorer.

The way I'm creating the file is completely dynamic depending on the
user's options.  Once this memory stream has been created, I'm
rendering on the screen.


This is where the problem is: The user sees the usual dialog which
says,


===========================================
'Some files can harm your computer, If the file information below
looks suspicious, or you do not fully trust the source, do not open or
save this file.


Filename: commands.amt


File Type: XYZ Company's Document Handler


From: localhost


Would you like to open the file or save it to your computer?'


[OPEN]                [SAVE]                [CANCEL]
[More Info]
=============================================


This is the problem.  I don't want to let the user click 'Open' every
time this happens and this happens quite a number of times in a day.


QUESTION:
----------------
How can I let my client tool pickup my "amt" file automatically
without the user having to click 'Open' every time?


I'm also including the different solutions I tried.


-=================================BEGIN==============================
        public void StreamMemoryStreamToClient(MemoryStream ms)
        {
            if (ms == null)
                return;


            //myPage.Response.ClearHeaders();
            //myPage.Response.ContentType = "application/amt";
            myPage.Response.Clear();
            //myPage.Response.OutputStream.Write(ms.GetBuffer(), 0,
ms.GetBuffer().Length);
            myPage.Response.AddHeader("content-disposition",
"attachment; filename=commands.amt");
            myPage.Response.BinaryWrite(ms.GetBuffer());
            //string newWindowScript = "<script language=JavaScript> "
+ script + " </script>";
            myPage.Response.End();
        }
-=================================END==============================
Environment: ASP.NET 2.0, windows client tool, IIS 5.0, Windows 2000.

I might be in the right direction if I start using 'EditFlags'.  If so, could someone help me how to do this using a 'Setup' project?

Thanks for the help!