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503 Valid RCPT Command Must Precede DATA
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If you are using Outlook as your email client and you are receiving the error ‘503 Valid RCPT command must precede DATA’, this indicates that the connection settings in your outlook are not properly authenticated by your email server.
The two most common causes for this error are:
1) Your email server requires you to check email first, before sending the email.
2) Your email client isn’t set up for SMTP Authentication.
In order to resolve this issue, you need to correct the connection settings in your outlook.
1) First, you need to open your “Account Settings’ in Outlook.

2) Then you need to select your email account that you want to change the email settings and click “Manage” or “Change” button.

3) Once you have the settings in front of you, click “More Settings” and then on the “Outgoing Server” tab.
4) Click on the “Outgoing Mail Server (SMTP) requires authentication” and make sure that “Use same settings as incoming mail server” is selected.

5) Then click on the “Advanced” tab and set the outgoing Port (SMTP) to 587. Then click “Ok” button.
Finally, you need to test “Account Settings”.
If you need any further help, please do reach our support department.
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