553 Requested action not taken: mailbox name not allowed

Meaning

The mailbox name is not allowed.

Common causes

• Invalid syntax.
• Policy block.

How to fix

1. Check address.

Example bounce

553 Requested action not taken: mailbox name not allowed

Related codes

• 553 5.1.2 Recipient domain not found
• 550 5.1.1 User unknown / invalid address
• 550 5.1.2 Bad destination system address