Hi,

I am building an application dat uses a (wse)webservice in two different
scenario's: within a domein and outside a domein, somewhere over the
internet.

Requests to the webservice need to be authenticated.

My approach: try to get a kerberos-ticket:
      
   private KerberosToken GetKerberosToken()
   {
       try
    {
        string targetPrincipalName = null;
        targetPrincipalName = "host/" + System.Net.Dns.GetHostName();
        return new KerberosToken(targetPrincipalName);
    }
    catch
    {
        return null;
    }
   }
                  
If this returns null, the application must be running outside the domein.
In this case a form pops up for the user to type his/her username/password.
In this case a usernametoken is setup and send to the webservice.

       proxy.SlimDossierWse _slimDOssier=new proxy.SlimDossierWse();
       _slimDOssier.RequestSoapContext.Security.Tokens.Add(new    
    UsernameToken("username@domein", "password",    
    PasswordOption.SendPlainText));

This works fine. Problem is that when I try to attach the kerberos ticket
to the webservice is this way:

       try
    {       
        proxy.SlimDossierWse _slimDOssier=new proxy.SlimDossierWse();
        _slimDOssier.ResponseSoapContext.Security.Tokens.Add(kerbToken);
     _slimDOssier.ResponseSoapContext.Security.Elements.Add(new
EncryptedData(kerbToken));               
    _slimDOssier.ResponseSoapContext.Security.Timestamp.TtlInSeconds=60;
                       
    }
    catch (Exception ex)
    {
        System.Windows.Forms.MessageBox.Show(string.Format("error: {0}
\n{1}",ex.Message, ex.Source));
    }

I keep getting this error: "object reference not set to an instance of an
object"

I cannot step through the code when this error occurs because my develop
machine is not within the domein, I can ony run the compiled version on a
computer in the domein.

Where am I going wrong?

Greetings,

Roland