RDP Session Credentials Validation

Question

I need a solution for setting username & password validation for my RDP Client application. The goal is to close the connection if the credentials (username or password) are incorrect.

How can I programmatically validate the session when one of the credentials is incorrect?

try
{
   rdp.Server = txtServer.Text;
   rdp.UserName = txtUserName.Text;

   IMsTscNonScriptable secured = (IMsTscNonScriptable)rdp.GetOcx();
   secured.ClearTextPassword = txtPassword.Text;

   rdp.OnLoginComplete += RdpOnOnLoginComplete;
   rdp.OnLogonError += rdp_OnLogonError;
   rdp.Connect();
}

catch (Exception Ex)
{
      MessageBox.Show("Error Connecting", "Error connecting to remote desktop " + txtServer.Text + " Error:  " + Ex.Message,MessageBoxButtons.OK, MessageBoxIcon.Error);
}

Events

void rdp_OnLogonError(object sender, AxMSTSCLib.IMsTscAxEvents_OnLogonErrorEvent e)
    {
       throw new NotImplementedException();
    }

private void RdpOnOnLoginComplete(object sender, EventArgs eventArgs)
    {
       throw new NotImplementedException();
    }

Answer 1

Importantly though, it seems that when using either the old TSAC control or the new RDPC control to connect to Server 2008 R2 (including Windows Home Server 2011) the control does not provide any "failed logon" feedback. I assume this was a security measure meant to help prevent hacking and cracking using these controls.

Unlike the stand-alone RDP Client utility program, a failed logon results in the connection being retained leaving the user looking at the remote system's logon desktop. This allows the user to manually logon on there but prevents a program from getting feedback on the logon failure and trying another user/password.

So... if your servers are all earlier than Server 2008 R2 you might still use one or the other of these controls to attempt an RDP connection and attempt a logon, reporting failure on bad credentials.