This does not always happen. The error occurs on this line.
FormsAuthenticationTicket authTicket = FormsAuthentication.Decrypt(authCookie.Value);
At this time the user if filling out a form that can bet used several times. The first one usually works, but after that this error may be thrown when the form is submitted .
HttpCookie authCookie = Request.Cookies[FormsAuthentication.FormsCookieName];
rider rd = new rider();
int rid;
FormsAuthenticationTicket authTicket = FormsAuthentication.Decrypt(authCookie.Value);
rid = Convert.ToInt32(authTicket.UserData);
The form submission causes the page (master) to go through this code every time it is submitted. Is that a problem?
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