ADFS : MSIS7042: The same client browser session has made '6' requests in the last '1' seconds.

Out of the blue, got this problem.

WTF?

So reviewed my changes to date.

I had made a change to fix the ubiquitous problem:

ID3206: A signin response may only redirect within the current web application

If you have played with WIF, you will have seen this particular problem.

The solution is BTW:

Add this to the global.asax

private void Application_BeginRequest(object sender, EventArgs e)
{
      if (String.Compare(Request.Path, Request.ApplicationPath,     StringComparison.InvariantCultureIgnoreCase) == 0 && !(Request.Path.EndsWith("/")))
                Response.Redirect(Request.Path + "/");
}

This seemed to have fixed the bug but then introduced another - the dreaded slippery slope.

After googling around, I found the problem.

In my ADFS RP, I had configured the endpoint without a trailing slash.

Added the missing "/" and all was well.

Enjoy!