Authentication failed during call webmethod from jquery.ajx with AspNet.FriendlyUrls and AspNet.Identity

Solution 1:

In your App_Start folder, within your RouteConfig....

Comment out the following line or change its RedirectMode:

//settings.AutoRedirectMode = RedirectMode.Permanent;

Solution 2:

It is not exactly the same use case, but worth mentioning if you are using a web service and had the "Authentication failed" message. Please check that your web service has the attribute "[System.Web.Script.Services.ScriptService]". This allows the web service to be called from script.

Example:

[System.Web.Script.Services.ScriptService]
public class WS_Default : System.Web.Services.WebService
{
    ...
}