HostMonster Web Hosting Help

503 Error - No longer able to send email and no changes were made


Sending email through Microsoft Outlook returns a bounce message containing the following reason:

"503 valid RCPT command must precede DATA"

The "Test Account Settings" button in Microsoft Outlook returns the following error:

Send test e-mail message: Unable to send test Message. Please verify the E-mail Address field.

Sending email through Mozilla Thunderbird returns the following error:

"An error occurred while sending mail. The mail server responded: The recipient cannot be verified. Please check all recipients of this message to verify they are valid. Please verify that your email address is correct in your Mail preferences and try again."


This error means that you will need to enable SMTP Authentication in your email client. When your Desktop email client attempts to send an email from our server it must authenticate. The Username and Password you would use would be the same as your incoming username and password.
Knowledgebase Article 82,686 views bookmark tags: bounce command data email precede rcpt send valid (updated 1136 days ago)

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