Unable to test sending email from .NET code in Windows Vista Business.

I am writing code which I will migrate to an SSIS Package once it its proven. The code is to send an error message via email to a list of recipients.

The code is below, however I am getting an exception when I execute the code.

I created a simple class to do the mailing... the design could be better, I am testing functionality before implementing more robust functionality, methods, etc.

namespace LabDemos { class Program { static void Main(string[] args) { Mailer m = new Mailer(); m.test();

    }
}

}

namespace LabDemos {

class MyMailer {

    List<string> _to = new List<string>();
    List<string> _cc = new List<string>();
    List<string> _bcc = new List<string>();
    String _msgFrom = "";
    String _msgSubject = "";
    String _msgBody = "";


    public void test(){
    //create the mail message
    MailMessage mail = new MailMessage();

    //set the addresses
    mail.From = new MailAddress("[email protected]");


    //set the content
    mail.Subject = "This is an email";
    mail.Body = "this is a sample body";
    mail.IsBodyHtml = false;



    //send the message
    SmtpClient smtp = new SmtpClient();
    smtp.Host = "emailservername";
    smtp.Port = 25;
    smtp.UseDefaultCredentials = true;
    smtp.Send(mail);

    }

}

Exception Message

Inner Exception {"Unable to read data from the transport connection: net_io_connectionclosed."}

Stack Trace " at System.Net.Mail.SmtpReplyReaderFactory.ProcessRead(Byte[] buffer, Int32 offset, Int32 read, Boolean readLine)\r\n at System.Net.Mail.SmtpReplyReaderFactory.ReadLines(SmtpReplyReader caller, Boolean oneLine)\r\n at System.Net.Mail.SmtpReplyReaderFactory.ReadLine(SmtpReplyReader caller)\r\n at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port)\r\n at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port)\r\n at System.Net.Mail.SmtpClient.GetConnection()\r\n at System.Net.Mail.SmtpClient.Send(MailMessage message)"

Outer Exception

System.Net.Mail.SmtpException was unhandled Message="Failure sending mail." Source="System" StackTrace: at System.Net.Mail.SmtpClient.Send(MailMessage message) at LabDemos.Mailer.test() in C:\Users\username\Documents\Visual Studio 2008\Projects\LabDemos\LabDemos\Mailer.cs:line 40 at LabDemos.Program.Main(String[] args) in C:\Users\username\Documents\Visual Studio 2008\Projects\LabDemos\LabDemos\Program.cs:line 48 at System.AppDomain._nExecuteAssembly(Assembly assembly, String[] args) at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args) at System.Runtime.Hosting.ManifestRunner.Run(Boolean checkAptModel) at System.Runtime.Hosting.ManifestRunner.ExecuteAsAssembly() at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext, String[] activationCustomData) at System.Runtime.Hosting.ApplicationActivator.CreateInstance(ActivationContext activationContext) at System.Activator.CreateInstance(ActivationContext activationContext) at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssemblyDebugInZone() at System.Threading.ThreadHelper.ThreadStart_Context(Object state) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state) at System.Threading.ThreadHelper.ThreadStart() InnerException: System.IO.IOException Message="Unable to read data from the transport connection: net_io_connectionclosed." Source="System" StackTrace: at System.Net.Mail.SmtpReplyReaderFactory.ProcessRead(Byte[] buffer, Int32 offset, Int32 read, Boolean readLine) at System.Net.Mail.SmtpReplyReaderFactory.ReadLines(SmtpReplyReader caller, Boolean oneLine) at System.Net.Mail.SmtpReplyReaderFactory.ReadLine(SmtpReplyReader caller) at System.Net.Mail.SmtpConnection.GetConnection(String host, Int32 port) at System.Net.Mail.SmtpTransport.GetConnection(String host, Int32 port) at System.Net.Mail.SmtpClient.GetConnection() at System.Net.Mail.SmtpClient.Send(MailMessage message) InnerException: