My application is built with Vb.net and we are getting an error when we bulk emails through SMTP. We are using<g class="gr_ gr_22 gr-alert gr_spell ContextualSpelling ins-del multiReplace" data-gr-id="22" id="22">appriver</g> credentials for SMTP userName and password.
When I am trying to send a series of emails one by one, getting an exception and the details as follow. The exception is coming after few emails have sent
ex.Message:
Syntax error, command unrecognized. The server response was: <User email> recipients flow control, try later
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Stack Trace:
at System.Net.Mail.RecipientCommand.CheckResponse(SmtpStatusCode statusCode, String response) at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify,
SmtpFailedRecipientException& exception) at System.Net.Mail.SmtpClient.Send(MailMessage message) at LeapSeedCommon.Utilities.Mailer.SendHTMLMailMessage(String mailFrom, String mailToName, String
mailSubject, String mailBody, ReaderProvider rpLocal, String mailCcName, String mailBccName, Attachment& oAttachment) at ASP.portal_admin_donor_names_filemanager_email_donor_names_aspx.btnEmailSend_Click(Object sender,
EventArgs e)
Please let me know that why this issue happening and suggest a solution.