503 Valid RCPT command must precede DATA

            March 28, 2020

503 Valid RCPT command must precede DATA Outlook Error for Mahahosting.com Account

This article is effective for all our users who are using

1) Mahahosting.com servers

2) RS Mahahosting Servers

3) Zimbra Mahahosting Server

4) Shared Servers

The errors may be

1) Bounce back message after sending email

2) Can be outlook send and receive error


"Sending' reported error (0x800CCC65) : 'Your outgoing (SMTP) e-mail server has reported an internal error. If you continue to receive this message, contact your server administrator or Internet service provider (ISP). The server responded: 503 Valid RCPT command must precede DATA'"

The reason for this issue is that your mail client fails to authenticate to the server. Generally, this is caused by the MS Outlook SMTP authentication is not switched on. Please refer to our Outlook tutorial, in order to set your MS Outlook client to use the proper authentication.

Another possible reason for the issue is an Antivirus or Firewall software which is checking your outgoing mail connections. In case you have set properly your mail client as explained above and the issue persists, please turn off the antivirus and the firewall software you have installed on your local computer and try sending out e-mails again.


When you send an email from Outlook you receive an error message:

503 Valid RCPT command must precede DATA”

How to fix the issue, its simple and takes less than 4mins to solve this by yourself.

Steps to fix “503 Valid RCPT command must precede DATA”

  1. > In Outlook, click File

  2. > Click Account Settings > Account Settings

  3. > Select your Mahahosting.com/Yourdomain.com email account.

  1. > Click Change

  2. > Click More Settings

  1. > Select the outgoing server tab from the TOP.

  2. > Check My outgoing server (SMTP) requires authentication

  3. > Select Use same settings as my incoming mail server

We hope with this simple test, you are able to solve the error.

IF you still face a issue, this means it requires more diagnostics and research, our team is always here to help you.,

We request you to create support ticket on the same.