The anti-forgery token could not be decrypted

Question

I have a form:

@using (Html.BeginForm(new { ReturnUrl = ViewBag.ReturnUrl })) {
@Html.AntiForgeryToken()
@Html.ValidationSummary()...

and a

Answer 1

If you get here from google for your own developer machine showing this error, try to clear cookies in the browser. Clear Browser cookies worked for me.