The provided anti-forgery token was meant for user "UserName", but the current user is ""

Question

When I am login with user's credential, first time no error while login to application,

but when I logoff and again login with other user's credential got an error

The provided anti-forgery token was meant for user "UserName", but the current user is "".

I am implementing AntiForgoryToken and IPrincipal with asp.net mvc 5

I tried :

1. AntiForgeryConfig.SuppressIdentityHeuristicChecks = true; in Application_Start()

2. I already refered this link When attempt logoff, The provided anti-forgery token was meant for user "XXXX", but the current user is ""

How can I fix this error ?

Thanks in advance.

Answer 1

I found my IIS instance had both Anonymous and Windows authentication enabled which was causing this exception for my application

Authentication Settings both enabled

This setting seems to be the cause of this exception. It seems that the ValidateAntiForgeryToken action filter was using the current user populated with an empty string in the Anon authentication and then attempting to match it against the token which was populated using Win authentication.

By turning off either Windows or Anonymous authentication (for my application I switched off Anon authentication,) the tokens now match up.

Authentication Settings one enabled

This setting can be altered in IIS manager or in the web.config file like so

<system.webServer>
    <security>
      <authentication>
        <anonymousAuthentication enabled="false" />
        <windowsAuthentication enabled="true" />
      </authentication>
    </security>
</system.webServer>