>>Hi,
>>
>>I've got my code to send email successfully using client.Send(msg), however when I try to do it using client.SendAsync(msg, userState) nothing happens.
>>
>>I have been following all the examples on the internet like this:
>>
>>http://msdn.microsoft.com/en-us/library/x5x13z6h.aspx
>>
>>My code runs through fine, no errors, just no email gets sent.
>
>Does the callback fire ? If so what's in the AsyncCompletedEventArgs ?

Here's my code, it appears to run through all the data that I expect and then sits at the waitHandle.WaitOne(); line and never goes into the SendCompletedCallback :

        public int PostAWBs()
        {
            string smtpClient = mmAppBase.AppSettingsMgr.GetSetting("SmtpClient");
            string smtpPort = mmAppBase.AppSettingsMgr.GetSetting("SmtpPort");

            int smtpPortInt = 25;
            bool resultport = Int32.TryParse(smtpPort, out smtpPortInt);

            string smtpFrom = mmAppBase.AppSettingsMgr.GetSetting("SmtpFrom");
            string smtpUser = mmAppBase.AppSettingsMgr.GetSetting("SmtpUser");
            string smtpPassword = mmAppBase.AppSettingsMgr.GetSetting("SmtpPassword");
            string smtpBCC = mmAppBase.AppSettingsMgr.GetSetting("SmtpBCC");

            string emailTest = mmAppBase.AppSettingsMgr.GetSetting("EmailTest");

            NetworkCredential cred = new NetworkCredential(smtpUser, smtpPassword);

            // get the Merge Template to use for Notification of Arrival
            MergeTemplateEntity mergeTemplate = MergeTemplate.GetMergeTemplateByCode("Arrival");


            // get all records from ManifestImport
            mmBindingList<ManifestImportEntity> ManifestImportList = this.ManifestImport.GetAllEntities();

            // for each record
            // Insert into AirWayBills
            // send email
            object numRemainingLock = new object();
            int numRemaining = ManifestImportList.Count;
            using (ManualResetEvent waitHandle = new ManualResetEvent(numRemaining == 0))
            {
                foreach (ManifestImportEntity ManifestImport in ManifestImportList)
                {
                    AirWayBillEntity awb = this.AirWayBill.NewEntity();
                    CustomerEntity customer = this.Customer.GetCustomerByCustomerNumber(ManifestImport.dls_acct.Substring(3)); // we do not store the country code as part of the customer code

                    // get the customer primary key
                    awb.awb_cusfk = customer.cus_PK;

                    int profileKey = 0;
                    bool result = Int32.TryParse(ManifestImport.profile_key, out profileKey);

                    awb.awb_keycode = profileKey;
                    awb.awb_manifestdate = ManifestHeaderImportList[0].man_date;
                    awb.awb_manifestnumber = ManifestHeaderImportList[0].man_number;
                    awb.awb_number = ManifestImport.awb;
                    awb.awb_pieces = ManifestImport.pieces;
                    awb.awb_value = ManifestImport.value; // need to calculate value
                    decimal weight = 0;
                    if (ManifestImport.weight != null)
                    {
                        weight = ManifestImport.weight.Value;
                    }
                    awb.awb_weight = Math.Ceiling(weight);
                    awb.awb_freight = ManifestImport.weight;  // need to calculate frieght
                    awb.awb_fuel = 0; // need to calculate fuel
                    awb.awb_insurance = 0; // need to calculate insurance
                    awb.awb_shipper = ManifestImport.shipper;
                    awb.awb_description = ManifestImport.description;


                    using (SmtpClient client = new SmtpClient(smtpClient, smtpPortInt))
                    {
                        client.SendCompleted += new SendCompletedEventHandler(SendCompletedCallback);

                        MailMessage msg = new MailMessage();

                        // Send to all email addresses for this customer
                        if (EmailAddress.EntityList.Count > 0)
                        {
                            foreach (EmailAddressEntity email in EmailAddress.EntityList)
                            {
                                if (emailTest == String.Empty)
                                {
                                    msg.To.Add(email.eml_email);
                                }
                                else
                                    msg.To.Add(emailTest);

                            }

                            if (smtpBCC != String.Empty)
                            {
                                msg.Bcc.Add(smtpBCC);
                            }

                            msg.From = new MailAddress(smtpFrom);
                            msg.Subject = mergeTemplate.mrg_subject;
                            string msgBody = mergeTemplate.mrg_template;

                            msg.Body = String.Format(msgBody, awb.awb_number, awb.awb_shipper, awb.awb_pieces, awb.awb_weight, awb.awb_value, awb.awb_description);
                            msg.IsBodyHtml = true;


                            client.Credentials = cred; // Send our account login details to the client.
                            client.EnableSsl = true;   
                            try
                            {
                                string userState = String.Format("Sending to {0}", customer.cus_firstname + customer.cus_lastname);
                                client.SendCompleted += delegate
                                {
                                    lock (numRemainingLock)
                                    {
                                        if (--numRemaining == 0)
                                        {
                                            waitHandle.Set();
                                        }
                                    }
                                };
                                client.SendAsync(msg, userState);                 // Send our email.   
                                //client.Send(msg);
                            }
                            catch (Exception)
                            {
                                msg.Dispose();
                                // throw;
                            }
                        }

                    }

                }
                waitHandle.WaitOne();
            }
// some more code to save things goes here
     }

        static bool mailSent = false;
        private static void SendCompletedCallback(object sender, AsyncCompletedEventArgs e)
        {
            // Get the unique identifier for this asynchronous operation.
            String token = (string)e.UserState;

            if (e.Cancelled)
            {
                Console.WriteLine("[{0}] Send canceled.", token);
            }
            if (e.Error != null)
            {
                Console.WriteLine("[{0}] {1}", token, e.Error.ToString());
            }
            else
            {
                Console.WriteLine("Message sent.");
            }
            mailSent = true;
        }