Exchange Web Services Managed API Error: Expected XML node type was XmlDeclaration, but actual type is Element

I have a simple test app to verify some functionality in Exchange Web Services Managed API. When Executing the code below I receive the error:

"Expected XML node type was XmlDeclaration, but actual type is Element"

I think I may have a permissions problem or some other issue but I have no idea where to look and an hoping someone has seen this before.
It looks like the error is being returned during the CertificateValidationCallback.


 The source code in C# is attached.

Any help would be appreciated. I have been beating my head against a wall on this one.

using System;
using System.Windows.Forms;
using Microsoft.Exchange.WebServices.Data;
using System.Net;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Net.Security;
using System.Security.Cryptography.X509Certificates;

namespace RestoreTest
{

    public partial class Form1 : Form
    {

        public Form1()
        {

            InitializeComponent();

        }

        private void Form1_Load(object sender, EventArgs e)
        {



        }

        public static bool CertificateValidationCallBack(object sender, System.Security.Cryptography.X509Certificates.X509Certificate certificate,
   System.Security.Cryptography.X509Certificates.X509Chain chain, System.Net.Security.SslPolicyErrors sslPolicyErrors)
        {

            // If the certificate is a valid, signed certificate, return true.
            if (sslPolicyErrors == System.Net.Security.SslPolicyErrors.None)
            {

                return true;

            }

            // If thre are errors in the certificate chain, look at each error to determine the cause.
            if ((sslPolicyErrors & System.Net.Security.SslPolicyErrors.RemoteCertificateChainErrors) != 0)
            {

                if (chain != null && chain.ChainStatus != null)
                {

                    foreach (System.Security.Cryptography.X509Certificates.X509ChainStatus status in chain.ChainStatus)
                    {
                        if ((certificate.Subject == certificate.Issuer) &&
                           (status.Status == System.Security.Cryptography.X509Certificates.X509ChainStatusFlags.UntrustedRoot))
                        {
                            // Self-signed certificates with an untrusted root are valid. 
                            continue;
                        }
                        else
                        {
                            if (status.Status != System.Security.Cryptography.X509Certificates.X509ChainStatusFlags.NoError)
                            {
                                // If there are any other errors in the certificate chain, the certificate is invalid,
                                // so the method returns false.
                                return false;
                            }
                        }
                    }

                }

                // When processing reaches this line, the only errors in the certificate chain are 
                // untrusted root errors for self-signed certifcates. These certificates are valid
                // for default Exchange server installations, so return true.
                return true;

            }
            else
            {

                // In all other cases, return false.
                return false;

            }

        }

        private void simpleButton1_Click(object sender, EventArgs e)
        {

            // Validate the server certificate.
            // For a certificate validation code example, see the Validating X509 Certificates topic in the Core Tasks section.            
            try
            {

                ServicePointManager.ServerCertificateValidationCallback = CertificateValidationCallBack;
                // Connect to Exchange Web Services as user1 at contoso.com.
                ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2007_SP1);
                service.Credentials = new WebCredentials("bob", "P@ssword123","icodecentral.local");
                service.Url = new Uri(@"https://localhost/EWS/Exchange.asmx");
                //service.AutodiscoverUrl("bob@icodecentral.local");

                // Create the e-mail message, set its properties, and send it to user2@contoso.com, saving a copy to the Sent Items folder. 
                EmailMessage message = new EmailMessage(service);
                message.Subject = "Interesting";
                message.Body = "The proposition has been considered.";
                message.ToRecipients.Add("claire@icodecentral.local");
                message.SendAndSaveCopy();

                // Write confirmation message to console window.
                MessageBox.Show("Message sent!");                

            }
            catch (Exception ex)
            {

                MessageBox.Show("Error: " + ex.Message);

            }

        }

    }
}

Select allOpen in new window