How to remove your IP from Unsubscore (LashBack UBL)

Unsubscore is the DNS zone for the LashBack Unsubscribe Blacklist. Here is what a listing means and how to get off it.

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What it is

The list, in plain terms.

Unsubscore is the DNS zone (ubl.unsubscore.com) that publishes the LashBack Unsubscribe Blacklist, or UBL, run by LashBack, LLC. It is an IP-based blocklist of roughly one million addresses, rebuilt hourly, that flags servers seen mailing addresses which should never have received mail.

LashBack seeds unsubscribe suppression files and mailing lists with monitored probe addresses — spam traps that exist only to catch senders who mail people who opted out or who were harvested. When your IP sends to one of those probes, the IP is listed. It is IP-based, so it is your sending server that is flagged, not the domain in your message.

The UBL is a niche list rather than a headline blocklist like Spamhaus. Some receivers and filtering appliances consult it, so a listing can cause deferrals or rejections at those sites, but its reach is narrower than the major zones. Treat a listing as a signal that your list hygiene or a compromised account has let mail reach addresses it should not.

Why you get listed

What a listing on Unsubscore (LashBack UBL) means.

Mailing a suppression-file address LashBack plants monitored addresses inside unsubscribe suppression files and lists. Sending to one of these probe addresses — often because a suppression or opt-out list was mishandled, shared or scraped — triggers a listing.

Harvested or purchased data Mailing addresses that were harvested, appended or bought rather than genuinely opted in is a common route onto the UBL, because such data frequently contains LashBack probe addresses.

A compromised or abused server A hijacked account, open relay or malware on the IP can send unsubscribe-probe or phishing traffic without your knowledge, which lands the IP on the list.

How to get removed

Delisting, in order.

Removal is free. Fix the cause first — a listing you clear without a fix comes straight back.

1 Confirm the listing. Look your sending IP up against ubl.unsubscore.com, or use the check on blacklist.lashback.com. A listing returns 127.0.0.2, meaning the IP mailed a LashBack unsubscribe probe address.
2 Find and fix the cause. Identify how mail reached a probe address: an unsuppressed opt-out, a purchased or appended list, a mishandled suppression file, or a compromised account or relay. Stop mailing that data and secure the server. Delisting before the cause is fixed only invites a fresh listing at the next hourly rebuild.
3 Submit a delist request. Use the delist request form on blacklist.lashback.com to ask for removal. A first-time removal is processed free of charge.
4 Or wait out the automatic removal. If no further probe hits are recorded, the IP is removed automatically after thirty days. This is the no-cost route if you have fixed the cause and are not in a hurry.
5 Re-check before resuming volume. Allow time for the hourly zone rebuild and DNS to propagate, then re-query ubl.unsubscore.com to confirm the IP is clear before you ramp sending back up.

The official route

Straight to the source.

Removal happens on Unsubscore (LashBack UBL)'s own tool — never through a paid service.

Unsubscore (LashBack UBL) removal tool ↗

Return codes

127.0.0.2 The IP sent email to a LashBack unsubscribe probe (spam-trap) address

How long it takes

A listed IP is removed automatically after thirty days with no further probe hits. A manual delist request via blacklist.lashback.com is free the first time; LashBack charges a fee for repeat removals on an IP that keeps re-offending. The zone rebuilds hourly, so allow up to an hour plus DNS propagation for a removal to take effect.

Common questions

About Unsubscore (LashBack UBL), specifically.

What is ubl.unsubscore.com? It is the DNS zone for the LashBack Unsubscribe Blacklist (UBL), operated by LashBack, LLC. An IP is listed when it sends mail to one of LashBack's monitored unsubscribe probe addresses.

Why is my IP on the LashBack UBL? Your server mailed an address that LashBack seeded into a suppression file or list as a trap. This usually means an opt-out was not honoured, a harvested or purchased list was used, or a compromised account on the IP sent probe or phishing traffic.

How do I remove my IP from Unsubscore? Fix the cause first, then submit a delist request on blacklist.lashback.com. Alternatively, if no further probe hits occur, the IP drops off automatically after thirty days.

Is removal free? A first-time removal is free. LashBack charges a fee for repeat removals where the same IP keeps re-offending. The thirty-day automatic removal is always free. Ignore any unrelated third party that offers to "remove" a blacklisting for a fee — only LashBack controls this list.

How long does removal take? The zone rebuilds hourly, so a processed delist request or the automatic thirty-day removal takes effect within about an hour plus DNS propagation. Re-query ubl.unsubscore.com to confirm.

How serious is a LashBack UBL listing? It is a niche list, so its reach is narrower than major blocklists like Spamhaus, but some receivers do consult it and can defer or reject your mail. More importantly it is a clear signal that your list hygiene or a compromised account needs attention.

The bounce behind the listing.

554 5.7.1 message rejected → The permanent bounce a listing most often triggers — what it means and how to clear it. 550 5.7.1 blocked → A rejection on reputation grounds — usually the same listing, seen from the sender side. Blacklist checker → Re-check your domain and every sending IP once the cause is fixed.

Do not fix it blind.

See every list you are on and every authentication problem behind the listing in one 40-second check — then let monitoring tell you the day a listing comes back.

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