This well known.
http://support.microsoft.com/?id=251404 Here is an explanation:
http://blogs.msdn.com/david.wang/archive/2005/12/01/HTTP-POST-Fails-for-Anonymous-Authentication.aspx
For the same reason that you complain about IE POSTing zero bytes, you
can complain that FireFox wastes bandwidth on authenticated requests
since the having/lacking the optimization causes both behaviors. It's
just that people tend to notice the IE behavior when doing custom
authentication (which while popular is often non-kosher).
//David
http://w3-4u.blogspot.com http://blogs.msdn.com/David.Wang //
On Mar 27, 5:11 pm, Skorccio <Skorc...@discussions.microsoft.com>
[quoted text, click to view] wrote:
> A particular scenario of IIS security settings causes a problem with IE
> browsers (v6 & v7) whereby no post data is sent to the server and the http
> header content-length is set to 0.
>
> To reproduce this behaviour, follow the steps below:
>
> 1) Create a web application with a default.aspx page containing a button
> such as,
> <asp:Button ID="testsubmit" runat="server" Text="test" />
> 2) Add the following code in the page_load event handler,
> if (this.IsPostBack)
> Response.Write("IsPostBack = true");
> else
> Response.Write("IsPostBack = false");
> 3) Set the home directory of the root website in iis6.0 to point to the
> above web application.
> 4) Set the root website (i.e. localhost) to iis integrated windows
> authentication.
> 5) Create a virtual directory below this (i.e. localhost/subdomain1) with
> the home directory pointing to the same folder as the root.
> 6) Set the virutal directory (i.e. subdomain1) to iis anonymous access.
> 7) Create another virtual directory below the root (i.e.
> localhost/subdomain2) with the home directory pointing to the same folder as
> the root.
> 8) Set the virutal directory (i.e. subdomain2) to iis integrated windows
> authentication. (we now have 3 identical web applications with one sub domain
> configured to anonymous access whilst the other two set to windows integrated
> authentication)
> 9) Open up IE v6 or v7.
> 10) Request the root website (i.e. localhost)
> 11) Submit form
> 12) Observe response value 'true'.
> 13) Request the virtual direcotry (i.e. localhost/subdomain1)
> 14) Submit form
> 15) Observe response value 'true'.
> 16) Request the virtual direcotry (i.e. localhost/subdomain2)
> 17) Submit form
> 18) Observe response value 'false'.
> 19) Repeat steps 9-17 with Firefox v2.
>
> Conclusion
>
> Content-length set to 0 by IE, no post data sent
> This behaviour can not be reproduced in Firefox v2.
>
> Any ideas why this ocurrs in IE?