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5.6.1 Media not supported

The server will not accept something in the message’s format or content type.

5.6.1 Media not supported

Permanent: retrying will not help

The server will not accept something in the message’s format or content type.

Usual causes
  • An unusual attachment type, or a malformed message structure.
What to do
  • Send plain text or standard HTML, and common attachment types such as PDF and PNG.

Usually the fault of: sender.

Common questions.

What does 5.6.1 mean?

The server will not accept something in the message’s format or content type.

Will retrying fix 5.6.1?

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 5.6.1?

Send plain text or standard HTML, and common attachment types such as PDF and PNG.

Other codes: 5.1.1 · 5.1.2 · 5.1.3 · 5.1.6 · 5.2.1 · 5.2.2 · 5.2.3 · 5.3.4 · Decode a whole bounce message

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