asp.net mvc - C# MVC "." Symbol in last position of the URL -

i have problem c# mvc 4, error 404 if symbol "." in last position of url, authentication api.

http://localhost/ws-avansys/api/avansys/authenticate/4551155/sannn21.

no problem if "." in position like:

http://localhost/ws-avansys/api/avansys/authenticate/4551155/sannn.21