Converting to CBA from CMA

You can convert a web application that has been configured to use CMA to use CBA, but only by using PowerShell. Once you convert the web application to use CBA, you cannot return to CMA. 

The following PowerShell commands will complete this conversion:

$ConvertApp = get-spwebapplication "http://<web application name>"

$ConvertApp.useclaimsauthentication = "True"
$ConvertApp.Update()