Error sending e-mail. Mailbox unavailable. The server response was: Please turn on SMTP Authentication in your mail client.

I have set up the email account for the shop.

While it can sent email to it's own domain it cannot sent to yahoo mail or Gmail accounts.

Full message:
System.Net.Mail.SmtpFailedRecipientException: Mailbox unavailable. The server response was: Please turn on SMTP Authentication in your mail client. 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 Nop.Services.Messages.EmailSender.SendEmail(EmailAccount emailAccount, String subject, String body, String fromAddress, String fromName, String toAddress, String toName, String replyTo, String replyToName, IEnumerable`1 bcc, IEnumerable`1 cc, String attachmentFilePath, String attachmentFileName, Int32 attachedDownloadId) at Nop.Services.Messages.QueuedMessagesSendTask.Execute()


The mailbox is working - It sent emails to other mail address from the same domain
Is there a setting fot the SMTP authentication ?
How can we fix this ?


Thank you in advance !

Solve it !
Password was incorrect !!!

hello sir,
i am using version 3.8 after configuring email account when i am going to test it i got this error.
Mailbox unavailable. The server response was: Please turn on SMTP Authentication in your mail client. (teamworkcrm)

how can i fix this?