## TL;DR
No unsubscribe link plus bulk volume is a textbook spam signal, and blocklists act fast. Halt all sending from the domain, request delisting, move future mail to a dedicated subdomain, and put a working one-click unsubscribe on every bulk message.

```text
agent sent 5000 cold emails with no unsubscribe link and the domain landed on a blocklist
```

## Use this when
- The domain appears on Spamhaus or a similar blocklist.
- Bulk cold sends bounce or vanish after a big push.
- Gmail's bulk sender rules flag the missing unsubscribe.

## Not for this skill when
- One-off emails landing in spam, which is content or reputation.
- Blocklists from compromised accounts sending phishing.
- IP-only listings where the domain itself is clean.

## Steps
1. Stop every send from the listed domain immediately. Verify: outbound queues for that domain are empty and paused.
2. Identify which blocklist listed the domain and read its delisting process. Verify: you can name the list and its removal steps.
3. Add a working one-click unsubscribe (List-Unsubscribe header plus a link) to the sending pipeline. Verify: a test email carries the header and the link unsubscribes.
4. Request delisting with evidence the cause is fixed. Verify: the lookup shows the domain clear.
5. Move bulk mail to a dedicated subdomain and warm it slowly; keep the root domain for transactional. Verify: the subdomain builds reputation over weeks, not days.

## Variant phrasings
### domain blocklisted after cold email
Common phrasing of the event.
### spamhaus delist domain cold email
The delisting-angle search.
### no unsubscribe link spam blocklist
The cause-angle search.

Compatibility: Any sending stack; blocklist operators and Gmail bulk-sender rules apply universally.

## Why it happens
Blocklists and Gmail's bulk sender guidelines treat missing unsubscribe as proof the mail is unsolicited. An agent that blasts thousands of messages with no opt-out trips automated listings within hours, and the domain's reputation follows it everywhere.

## Edge cases / pitfalls
- Delisting without fixing the cause gets you relisted faster.
- Buying a fresh domain to dodge the listing restarts the reputation clock at zero.
- Bulk email laws require opt-out; this is legal exposure, not just deliverability.
- Suppression lists must persist across the subdomain move; do not re-mail people who opted out.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_uOdj0JZyZdG1cCANSHrJJw