554 Transaction failed

Meaning

The transaction failed for an unspecified reason (often spam block).

Common causes

• Spam block.
• Blacklisted IP.

How to fix

1. Check reputation.
2. Fix authentication.

Example bounce

554 Transaction failed

Related codes

• 554 5.7.1 Message rejected / Spam block
• 554 5.3.3 System not capable of selected features
• 550 5.4.1 Recipient address rejected: Access denied