Mail Error 503 valid RCPT command must precede DATA

When sending email, if you receive an immediate bounceback, such as the following:





The following recipient(s) could not be reached:

'John Smith' on DATE/DATE/DATE

503 valid RCPT command must precede DATA




This means that before sending email, you must set up authentication, which is required by dotCanada's mail servers. To do this, simply follow these steps:

POP before SMTP

Action: Check your email for new mail before trying to send out any email.

What this does: This adds your IP address to a relayhosts file and allows any email to be sent from that IP address for up to 30 minutes. After 30 minutes, you have to authenticate again.

Configure your email client to authenticate automatically

Action: Check the "my server requires authentication" box in your email configuration.

What this does: You will be able to send mail without having to "pop" your mail box first.

If using Microsoft Outlook, please try the following:

Open Outlook.

Go to Tools > Email Accounts.

Select the Account that 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.

If it fails on Send, then repeat these steps:

Click on "Advanced Tab".

Set outgoing Port (SMTP) to 26.

Click OK and then Test Account Settings.

If you are still having difficulty, please contact dotCanada technical support for additional help.

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