503 Valid RCPT command must precede DATA
- You will get that error message if your mail client is not properly
configured. To be exact, you missed to enable the option “My SMTP server
requires authentication”. Once you enable it you will not see the error
anymore.
- Your firewall/antivirus system may cause that error to appear as well. If the error persists after enabling SMTP authentication in your mail client, try disabling your firewall/antivirus.
Why SMTP authentication is required?
If Website.com.bn mail servers do not require authentication spammers
will be able to use them to send SPAM. Only authorized users can access
the mail server to send messages. We do not allow any kind of open
relays. In that way we keep our mail server IP’s clean and will be able maintain its reputation score.