The request was aborted Could not create SSL TLS secure channel

Question

When I connect to an  HTTPS server using WebRequest, I am facing an error.

The request was aborted: Could not create SSL/TLS secure channel.

I used this code to bypass this error:

private void Somewhere() {
    ServicePointManager.ServerCertificateValidationCallback += new RemoteCertificateValidationCallback(AlwaysGoodCertificate);
}

private static bool AlwaysGoodCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors policyErrors) {
   return true;
}

The server never validates the certificate and fails with the above error. Does anyone have any idea of what I should do?