backport #35833
@ -128,7 +128,7 @@ func (s *SMTPSender) Send(from string, to []string, msg io.WriterTo) error {
return fmt.Errorf("failed to issue MAIL command: %w", err)
}
} else {
if err = client.Mail(from); err != nil {
if err = client.Mail(fmt.Sprintf("<%s>", from)); err != nil {