550 that SMTP username's account is not allowed to send

This also applies if you encounter: 550 that IP address is not allowed to send

The situations where you will encounter these errors are:

The account you are trying to send through is currently closed.
This will displayed on your main dashboard page when logged in. You will need to reopen your account to be allowed to send - please see our Reopening a Closed Account article for instructions.


The SMTP User, API Key or authenticated IP address (IP Authentication) is currently blocked.
You will need to change the "User Status" for the SMTP User, API Key or IP Address to "Allowed" in the respective section:

  • SMTP User:
    Sending > SMTP Users > select the username > go to "Tracking & Status" and set it to "Allowed".

  • API Key:
    Sending > API Keys > select the API Key > go to "Tracking & Status" and set it to "Allowed".

  • IP Authentication:
    Sending > IP Authentication > select the IP Address > go to "Tracking & Status" and set it to "Allowed".

Note: In situations where suspicious sending activity has occurred (e.g. spam outbreak) in your account, our review team may temporarily block the offending SMTP User, API Key or IP Address until the issue has been resolved. Our review team will contact you via email ticket with information and ask you to investigate.

If you have further questions regarding these errors or other parts of the SMTP2GO service, please contact our friendly support team for assistance.

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