553 5.7.2 [TSS09]
TSS09 Permanent Block
Yahoo permanently deferred all messages from this IP or domain. Retrying will not work.
TSS09 indicates Yahoo saw significant abuse or policy violations. You must fix the root cause and provide evidence before delisting.
Severity
CRITICAL
Provider
Yahoo Mail
Reference
TSS09
Last Reviewed
2025-06-01
How to Fix 553 5.7.2 [TSS09]
Follow these steps to resolve this Yahoo Mail SMTP error and restore normal delivery.
- ✓Stop sending immediately and audit infrastructure for compromise.
- ✓Resolve complaint, trap, and bounce issues across every list source.
- ✓Submit a detailed mitigation request through the Yahoo Sender Hub.
- ✓When approved, restart with small, highly engaged segments.
Helpful Resources
More Yahoo Mail SMTP Codes
Keep these related troubleshooting guides handy while addressing 553 5.7.2 [TSS09].
Still experiencing Yahoo Mail delivery issues?
Run your domain through our free deliverability tools or book a session with Bento's deliverability specialists.