System.Net.Mail.SmtpException: The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.57 Client not authenticated to send mail. Error: 535 5.7.3 Authentication unsuccessful [BN9PR03CA0673.namprd03.prod.outlook.com 2026-08-07T12:04:19.050Z 08DEF455543F34EB]
   at System.Net.Mail.MailCommand.CheckResponse(SmtpStatusCode statusCode, String response)
   at System.Net.Mail.MailCommand.Send(SmtpConnection conn, Byte[] command, MailAddress from, Boolean allowUnicode)
   at System.Net.Mail.SmtpTransport.SendMail(MailAddress sender, MailAddressCollection recipients, String deliveryNotify, Boolean allowUnicode, SmtpFailedRecipientException& exception)
   at System.Net.Mail.SmtpClient.Send(MailMessage message)
   at XDevGroup.CMS.www.Global_asax.Application_Error(Object sender, EventArgs e) in C:\Data\XDevGroup\Source Code\XDevGroup.CMS\XDevGroup.CMS.www\Global.asax.vb:line 444