MailFixIt

Yahoo SMTP delivery response

Resolve Yahoo TSS07: Sending IP listed by Spamhaus

Yahoo is refusing connections from the cited sending IP because the response says that IP appears on a Spamhaus list.

Problem description

A representative response is:

553 5.7.1 [TSS07] Connections will not be accepted from [IP], because the IP is in Spamhaus's list.
Is this temporary or permanent?

This is permanent. Stop retries and correct the IP listing cause before testing Yahoo again.

What this response means

A representative response is 553 5.7.1 [TSS07] Connections will not be accepted from [IP], because the IP is in Spamhaus's list. This is a permanent source-IP rejection, not a bad-recipient bounce.

Fix it

  1. Copy the exact connecting IP, Spamhaus list or lookup reference, full Yahoo response, and timestamp.
  2. Identify who controls that outbound IP. If it belongs to a shared email service, open a provider case instead of attempting changes to your website IP.
  3. Use the official Spamhaus lookup for that IP and follow the remediation for the specific list shown.
  4. Stop compromised accounts, malware, open proxy or relay behavior, unsolicited mail, and repeated invalid-recipient traffic before requesting removal.
  5. Verify forward-confirmed reverse DNS, HELO identity, SPF, DKIM, and DMARC as supporting sender hygiene.
  6. After delisting propagates, send a small controlled Yahoo test and monitor for recurrence.

Do not pay an unrelated third party for guaranteed delisting and do not move unchanged abusive traffic to another IP.

What MailFixIt can check

MailFixIt can inspect public authentication and DNS identity. It cannot remove a Spamhaus listing or change Yahoo’s receiver state.

Use the Yahoo sender-requirements guide to verify the source before resuming normal traffic.

Frequently asked questions

What does Yahoo TSS07 sending IP listed by Spamhaus mean?

Yahoo rejected the connecting IP because the response identifies a Spamhaus listing. The IP owner must investigate and follow the listing-specific removal process.

Can MailFixIt prove this entire bounce from public DNS?

No. The current checker can evaluate selected public DNS configuration, but it cannot recreate recipient state, credentials, reputation, message content, or a historical provider SMTP decision.

Related email diagnostics

Yahoo Sender Requirements and RecommendationsCheck Yahoo and AOL sender requirements for authentication, DMARC alignment, PTR, spam rate, message format and one-click unsubscribe. Yahoo: Message temporarily deferred (TS* errors)Resolve Yahoo Message temporarily deferred and TS* errors by slowing retries and finding the affected traffic or reputation signal.

Primary sources: Yahoo SMTP error codes.