ASP.NET MVC: Unauthenticated User Always Redirected to ~/Account/LogOn Despite Custom Sign In Url

By default new ASP.NET MVC projects redirect any unauthenticated users who request resources that require authentication to the /Account/LogOn action. The log on page is defined in the web.config authentication section.

<authentication mode="Forms">
  <forms loginUrl="~/Account/LogOn" timeout="2880" />

It is my preference for users to “Sign in” instead of “Log on” so I changed the web.config to the following and changed the action method name from LogOn to SignIn.

<authentication mode="Forms">
  <forms loginUrl="~/Account/SignIn" timeout="2880" />

After the change I tried accessing a page that required the user to be authorized with and unauthorized user and to my surprise, the site redirected me to /Account/LogOn and I got a 404 error saying the the resource could not be found. It turns out this is a known issue with the ASP.NET MVC when the WebMatrix.Data.dll and WebMatrix.DataWeb.dll are added to the deployable assemblies collection. This issue can be fixed by adding the following key to the appSettings section of the web.config.

  <add key="loginUrl" value="~/Account/SignIn" />

I presume this will be fixed in the next release of ASP.NET MVC as a bug has been logged on Microsoft Connect here.