C# Exchange 2007 Transport Agent

Im trying to write an exchange transport agent that tests to see if the subject line is empty, if it is than it inserts a default subject line. whenever i compiled, installed, and enabled this dll the server would no longer route email...

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;
using Microsoft.Exchange.Data.Transport;
using Microsoft.Exchange.Data.Transport.Email;
using Microsoft.Exchange.Data.Transport.Smtp;
using Microsoft.Exchange.Data.Transport.Routing;
using Microsoft.Exchange.Data.Common;

namespace ExchangeTransportAgent
{
    public class RoutingFactory : RoutingAgentFactory
    {

        public override RoutingAgent CreateAgent(SmtpServer server)
        {
            RoutingAgent myAgent = new sRoutingAgent();
            return myAgent;
        }
    }
}




class sRoutingAgent : RoutingAgent
{

    public sRoutingAgent()
    {
        //subscribe to different events
        base.OnSubmittedMessage += new SubmittedMessageEventHandler(SRoutingAgent_OnSubmittedMessage);
    }

    void SRoutingAgent_OnSubmittedMessage(SubmittedMessageEventSource source, QueuedMessageEventArgs e)
    {
        if (e.MailItem.Message.Subject == string.Empty)
        {
            try
            {
                e.MailItem.Message.Subject = "Kranichs Jewelers";


                EventLog.WriteEntry("MY Exchange Routing Agent", "MY ROUTING AGENT CHANGED THE SUBJECT",
                EventLogEntryType.Information, 1开发者_如何学Python337);
            }
            catch (Exception except)
            {
                EventLog.WriteEntry("MY Exchange Routing Agent", except.Message,
                    EventLogEntryType.Error);
            }
        }
    }

}

does anyone know why this might not be working?

thanks

"EventLog.WriteEntry" throw an error maybe. I had the same problem and when remove "EventLog.WriteEntry" all was ok. For now I don't know why.