5.1.6 Mailbox has moved

The recipient has a new address, and the old one no longer works.

5.1.6 Mailbox has moved

Permanent: retrying will not help

The recipient has a new address, and the old one no longer works.

Usual causes

The person moved to another account or provider.

What to do

Ask the person for their new address and update your records.

Usually the fault of: recipient.

Common questions.

What does 5.1.6 mean?

The recipient has a new address, and the old one no longer works.

Will retrying fix 5.1.6?

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 5.1.6?

Ask the person for their new address and update your records.

Other codes: 5.1.1 · 5.1.2 · 5.1.3 · 5.2.1 · 5.2.2 · 5.2.3 · 5.3.4 · 5.4.1 · Decode a whole bounce message

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