ASP.NET

Using memoryStream As New MemoryStream()
   Dim sData As String = "" ' getDataFromFile()

   For i = 1 To 2342
     sData += "A"
   Next

   Dim contentAsBytes As Byte() = Encoding.UTF8.GetBytes(sData)

   memoryStream.Write(contentAsBytes, 0, contentAsBytes.Length)
   ' Set the position to the beginning of the stream.
   memoryStream.Position = 0

   ' Create attachment
   Dim contentType As New ContentType()
   contentType.MediaType = MediaTypeNames.Application.Octet
   contentType.Name = "attachment.xls"

   Dim attachment As New Attachment(memoryStream, contentType)
                    
   ' Add the attachment
   message.Attachments.Add(attachment)

   ' Send Mail via SmtpClient
   smtpClient.Send(message)
End Using

System.Net.Mail.SmtpException was unhandled by user code<br />
  Message="Failure sending mail."<br />
  Source="System"<br />
  StackTrace:<br />
       at System.Net.Mail.SmtpClient.Send(MailMessage message)    at _SendMail.btnSendMail_Click(Object sender, EventArgs e) in E:\Visual Studio 2008\XlsMail\Default.aspx.vb:line 55    at System.Web.UI.WebControls.Button.OnClick(EventArgs e)    at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument)    at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument)    at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument)    at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData)    at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)<br />
  InnerException: System.IO.IOException<br />
       Message="Unable to read data from the transport connection: A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond."<br />
       Source="System"<br />
       StackTrace:<br />
            at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)    at System.Net.DelegatedStream.Read(Byte[] buffer, Int32 offset, Int32 count)    at System.Net.BufferedReadStream.Read(Byte[] buffer, Int32 offset, Int32 count)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLines(SmtpReplyReader caller, Boolean oneLine)    at System.Net.Mail.SmtpReplyReaderFactory.ReadLine(SmtpReplyReader caller)    at System.Net.Mail.CheckCommand.Send(SmtpConnection conn, String& response)    at System.Net.Mail.DataStopCommand.Send(SmtpConnection conn)    at System.Net.Mail.SmtpConnection.OnClose(Object sender, EventArgs args)    at System.Net.ClosableStream.Close()    at System.Net.Mail.MailWriter.Close()    at System.Net.Mail.SmtpClient.Send(MailMessage message)<br />
       InnerException: System.Net.Sockets.SocketException<br />
            ErrorCode=10060<br />
            Message="A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond"<br />
            NativeErrorCode=10060<br />
            Source="System"<br />
            StackTrace:<br />
                 at System.Net.Sockets.Socket.Receive(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)    at System.Net.Sockets.NetworkStream.Read(Byte[] buffer, Int32 offset, Int32 size)<br />
            InnerException: 

    using (OleDbCommand dcmd = new OleDbCommand("SELECT * FROM " + strUPloadFile + "", dconn))
    {
        try
        {
            dconn.Open();

            using (OleDbDataReader dreader = dcmd.ExecuteReader())
            {

                // Bulk Copy to SQL Server
                using (SqlBulkCopy bulkCopy = new SqlBulkCopy(WebConfigurationManager.ConnectionStrings["######"].ConnectionString))
                {
                    //bulkCopy.ColumnMappings.Add("adds_ABMId", 45);
                    bulkCopy.ColumnMappings.Add("adds_Email", "E-mail Address");
                    bulkCopy.ColumnMappings.Add("adds_RecipientForename", "First Name");
                    bulkCopy.ColumnMappings.Add("adds_RecipientSurname", "Last Name");

                    bulkCopy.DestinationTableName = "tbl_AddressBookAddresses";

                    // Set the BatchSize.
                    bulkCopy.BatchSize = 500;
                    try
                    {//perform copy
                        bulkCopy.WriteToServer(dreader);
                    }
                    catch (Exception ex)
                    {//error
                        throw(ex);
                    }
                }

            }
        }
        finally
        {
            dconn.Close();
        }
    }
}