530 Authentication required

The server will not accept the message until you log in.

530 Authentication required

Permanent: retrying will not help

The server will not accept the message until you log in.

Usual causes

You are sending through a server that needs a username and password or an API key, and none was sent.
The wrong port or security setting, so the login step never happened.

What to do

Add your login details to the sending settings.
Use the port and encryption your provider documents (for example 587 with STARTTLS, or 465 with SSL).

Usually the fault of: sender.

Common questions.

What does 530 mean?

The server will not accept the message until you log in.

Will retrying fix 530?

No. It is a permanent failure, so retrying the same message will not help, and repeated attempts can hurt your sending reputation. Fix the cause first.

How do I fix 530?

Add your login details to the sending settings. Use the port and encryption your provider documents (for example 587 with STARTTLS, or 465 with SSL).

Other codes: 250 · 421 · 450 · 451 · 452 · 500 · 501 · 503 · Decode a whole bounce message

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