Battling To Programmatically Load A Report

Hi friends,

I am struggling to programmatically render my report to a pdf without displaying it in a viewer and would appreciate a pointer in the right direction.

My code seems to work and the report is found and everything is honkey-dorey until I try to actually load the report.. lemme show: (please excuse the bit of a mess since this is just a test form)

rs = new rs2005.ReportingService2005();
rsExec = new rsExecService.ReportExecutionService();
// Prepare Render arguments
string historyID = null;
string deviceInfo = null;
string format = "PDF";
Byte[] results;
string encoding = String.Empty;
string mimeType = String.Empty;
string extension = String.Empty;
rsExecService.Warning[] warnings = null;
string[] streamIDs = null;

// Define variables needed for GetParameters() method
string _historyID = null;
bool _forRendering = false;
rs2005.ParameterValue[] _values = null;

// Authenticate to the Web service using Windows credentials
rs.Credentials = System.Net.CredentialCache.DefaultCredentials;
rsExec.Credentials = System.Net.CredentialCache.DefaultCredentials;

rs2005.DataSourceCredentials[] _credentials = null;
rs2005.ReportParameter[] _parameters = null;

FindReport();
//Create a variable containing the selected item
selItem = MyCatalogItem.Item;
try
{
// Get if any parameters needed.
_parameters = rs.GetReportParameters(selItem.Path , _historyID, _forRendering, _values, _credentials );

// Load the selected report.
rsExecService.ExecutionInfo ei = rsExec.LoadReport(selItem.Path, historyID);

// Prepare report parameter.
// Set the parameters for the report needed.
rsExecService.ParameterValue[] parameters = new rsExecService.ParameterValue[5];

// Place to include the parameter..
if (_parameters.Length > 0)
{
parameters[0] = new rsExecService.ParameterValue();
parameters[0].Value = pQuoteID.ToString();
parameters[0].Label = "Quote ID";
parameters[0].Name = "cor_Quote_id";

parameters[1] = new rsExecService.ParameterValue();
parameters[1].Value = DateTime.Now.ToString();
parameters[1].Label = "Quote Start Period";
parameters[1].Name = "QuoteStartPeriod";

parameters[2] = new rsExecService.ParameterValue();
parameters[2].Value = DateTime.Now.ToString();
parameters[2].Label = "Quote End Period";
parameters[2].Name = "QuoteEndPeriod";

parameters[3] = new rsExecService.ParameterValue();
parameters[3].Value = "Client";
parameters[3].Label = "Client";
parameters[3].Name = "ClientName";

parameters[4] = new rsExecService.ParameterValue();
parameters[4].Value = "Ralph Contact";
parameters[4].Label = "Ralph Contact";
parameters[4].Name = "RaljacContact";

}
rsExec.SetExecutionParameters(parameters, "en-us");
results = rsExec.Render(format, deviceInfo, out mimeType, out encoding, out warnings, out streamIDs);

// Create a file stream and write the report to it
using (FileStream stream = File.OpenWrite(fileName))
{
stream.Write(results, 0, results.Length);
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}

Right, It bombs out at the section I marked in blue and gives me this HUGE message :

"System.Web.Services.Protocols.SoapException: Server did not recognize the value of HTTP Header SOAPAction: http://schemas.microsoft.com/sqlserver/2005/01/12/reporting/reportingservices/LoadReport.
at System.Web.Services.Protocols.Soap11ServerProtocolHelper.RouteRequest()
at System.Web.Services.Protocols.SoapServerProtocol.RouteRequest(SoapServerMessage message)
at System.Web.Services.Protocols.SoapServerProtocol.Initialize()
at System.Web.Services.Protocols.ServerProtocolFactory.Create(Type type, HttpContext context, HttpRequest request, HttpResponse response, Boolean& abortProcessing)"

Could this be related to credentials or something? Any advice welcome.
Thanks Mates