CrmImpersonator and IFD

'Microsoft.Crm.WebServices.Crm2007.CookieAndSoapHeaderAuthenticationProvider, Microsoft.Crm.WebServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' doesn't exist.
Parameter name: Microsoft.Crm.WebServices.Crm2007.CookieAndSoapHeaderAuthenticationProvider, Microsoft.Crm.WebServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ArgumentException: 'Microsoft.Crm.WebServices.Crm2007.CookieAndSoapHeaderAuthenticationProvider, Microsoft.Crm.WebServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35' doesn't exist.
Parameter name: Microsoft.Crm.WebServices.Crm2007.CookieAndSoapHeaderAuthenticationProvider, Microsoft.Crm.WebServices, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35

public string orgname;
    public string crmurl;
    public string metaurl;
    public bool offline;

    protected void Page_Load(object sender, EventArgs e)
    {
        #region CRM URLs and Organization Name

        //Determine Offline State from Host Name
        if (Request.Url.Host.ToString() == "127.0.0.1")
        {
            #region offline
            offline = true;

            //Retrieve the Port and OrgName from the Registry
            //RegistryKey regkey = Registry.CurrentUser.OpenSubKey("Software\Microsoft\MSCRMClient");
            //orgname = regkey.GetValue("ClientAuthOrganizationName").ToString();
            string portnumber = regkey.GetValue("CassiniPort").ToString();

            //Construct the URLs
            string baseurl = "http://localhost:" + portnumber + "/mscrmservices/2007/";
            crmurl = baseurl + "crmservice.asmx";
            metaurl = baseurl + "metadataservice.asmx";
            #endregion
        }
        else
        {
            offline = false;

            //Retrieve the URLs from the Registry
            //RegistryKey regkey = Registry.LocalMachine.OpenSubKey("SOFTWARE\Microsoft\MSCRM");
            //string ServerUrl = regkey.GetValue("ServerUrl").ToString();
            string ServerUrl = "http://192.168.1.152:5555/MSCRMServices";
            crmurl = ServerUrl + "/2007/crmservice.asmx";
            metaurl = ServerUrl + "/2007/metadataservice.asmx";
            Response.Write("ServerURL " + ServerUrl + "<br>");
            Response.Write("CRMURL:   " + crmurl + "<br>");
            Response.Write("MetaURL:  " + metaurl + "<br>");

            //Retrieve the Query String from the current URL
            if (Request.QueryString["orgname"] == null)
            {
                orgname = string.Empty;
            }
            else
            {
                //Query String
                string orgquerystring = Request.QueryString["orgname"].ToString();
                if (string.IsNullOrEmpty(orgquerystring))
                {
                    orgname = string.Empty;
                }
                else
                {
                    orgname = orgquerystring;
                }

            }

            if (string.IsNullOrEmpty(orgname))
            {
                //Windows Auth URL
                if (Request.Url.Segments[2].TrimEnd('/').ToLower() == "isv")
                {
                    orgname = Request.Url.Segments[1].TrimEnd('/').ToLower();
                }

                //IFD URL
                if (string.IsNullOrEmpty(orgname))
                {
                    string url = Request.Url.ToString().ToLower();
                    int start = url.IndexOf("://") + 3;
                    orgname = url.Substring(start, url.IndexOf(".") - start);
                }
            }
            Response.Write(orgname + "<br>");
        }

        #endregion
    }

Execute as user =@username
Select * from FilteredActivityPointer;
revert