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5.5.2 Syntax error

A command or address was written in a way the server cannot read.

5.5.2 Syntax error

Permanent: retrying will not help

A command or address was written in a way the server cannot read.

Usual causes
  • A malformed address or header.
  • A script that builds SMTP commands by hand.
What to do
  • Check addresses and headers for stray characters, and use a mail library.

Usually the fault of: sender.

Common questions.

What does 5.5.2 mean?

A command or address was written in a way the server cannot read.

Will retrying fix 5.5.2?

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 5.5.2?

Check addresses and headers for stray characters, and use a mail library.

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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