Cannot access a disposed object named System.Net.TlsStream

[Mackuack]

Hello everybody

i have the following code to access an application via https:

---------------------------------------------
System.Net.ServicePointManager.CertificatePolicy = new
TrustAllCertificatePolicy();

httpWebRequest = (HttpWebRequest)WebRequest.Create(url);

X509Certificate cer =
X509Certificate.CreateFromCertFile(@"c:\Certificad oCliente.cer");

httpWebRequest.ClientCertificates.Add(cer);
httpWebRequest.Method = "POST";
httpWebRequest.ContentLength = stringPost.Length;

streamWriter = new StreamWriter(httpWebRequest.GetRequestStream());

streamWriter.Write(stringPost);
streamWriter.Close();

HttpWebResponse httpWebResponse =
(HttpWebResponse)httpWebRequest.GetResponse();
StreamReader streamReader = new
StreamReader(httpWebResponse.GetResponseStream());
respuesta = streamReader.ReadToEnd();
streamReader.Close();
---------------------------------------------

Although the connection is created (i think the certificates are
correctly installed), i got an exception when i try to close the
streamWriter:

"Cannot access a disposed object named \"System.Net.TlsStream\"."

As you can see i have created the TrustAllCertificatePolicy class, but
i still get that exception. Could anyone help me?

Thanks in advance. Patricio.