Fix 503 Valid RCPT command must precede DATA in Outlook

Fix 503 Valid RCPT command must precede DATA in Outlook

503 Valid RCPT command must precede DATA essentially means that the server was unable to accept the message, usually because the SMTP connection was not properly authenticated. In cPanel servers, authentication can happen either through POP-before-SMTP or through SMTP authentication. If the user has not configured Outlook for outgoing mail SMTP authentication, and has not connected to the POP server before sending the mail, this error is returned.

To fix this :

  1. In Outlook, click File
  2. Click Account Settings > Account Settings
  3. Select your email account.
  4. Click Change…
  5. Click More Settings…
  6. Select the Outgoing Server tab
  7. Check 'My outgoing server (SMTP) requires authentication'
  8. Select 'Use same settings as my incoming mail server'


     
  9. Switch to the Advanced tab
  10. Change the outgoing server (SMTP) port to 465
  11. Set 'Use the following type of encrypted connection' to OK




  12. Click OK
  13. Click Next
Last update on: 2017-03-27 08:54:28