How to load HTML page in Iframe (firefox)

Question

Hi All,

1. I have an Iframe with Runat="server" value.
2. I have Html Pages in HTML Folder.
3. Loading HTML page in inframe via button click like below

iframe.Attributes["src"] = @"HTML\file.htm";

It works fine in IE why not in Firefox..Is there anything to provide to load in FF?

Firefox throws Bad Request error inside Iframe:-(

Note: Am running application in local only

Advanced Thanks
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