Error: 503 Valid RCPT command must precede DATA
If using Microsoft Outlook, please try the following:
- Open Outlook.
- Go to Tools > Email Accounts.
- Select the Account tht is causing you trouble and click “Change”.
- Click on More Settings.
- Click on Outgoing Server Tab.
- Click “Outgoing Mail Server (SMTP) requires authentication” and make sure “Use same settings as incoming mail server” is selected.
- Click on “Advanced Tab”.
- Set outgoing Port (SMTP) to 587.
- Click OK and then Test Account Settings.