Dears i have many clients that are using RPC over https today i have decide to deploy the Form Based Authentication , but all of our RPC clients faced problems and can't access , can you kinfdly adivce what is this issuejohn yassa

Hello John, Could you please go to: https://www.testexchangeconnectivity.com/Default.aspx and then select the RPC over HTTP check. This will give you more information regarding your problem. After running this test you can post the problem description over here so I can take a look at it. regards, Peter