SORBS Blacklist Removal

By DrGlenn — USA-based WordPress security specialist· 290+ cleanups across 34 countries· Updated September 28, 2026

You cannot get delisted from SORBS, because SORBS no longer exists. Proofpoint, which owned it, decommissioned the service on June 5, 2024 and emptied every one of its DNS zones. As of September 2026 the sorbs.net domain itself no longer resolves. If a tool, a bounce message or an audit report still says you are “listed on SORBS”, the report is stale — and the useful question is what is actually blocking your mail, if anything is.

What happened to SORBS

SORBS — the Spam and Open Relay Blocking System — was one of the longest-running DNS blocklists, started in 2001 and used by a large number of mail servers to reject spam from listed IP addresses. On June 5, 2024 Proofpoint announced it was sunsetting the service. The zones were emptied, so for a while lookups simply came back clean. Since then the domain has lapsed entirely: when I checked in September 2026, public resolvers returned “non-existent domain” for sorbs.net and for its blocklist zones.

There was no successor list, no migration and no delisting form left behind. Anything that still presents a SORBS result is either reading an old cache, running an out-of-date list of blocklists, or quoting a bounce message from before the shutdown.

Why you still see SORBS in 2026

• Old multi-blacklist checkers. Some “check 100 blacklists at once” tools still have SORBS in their list and show it as an error, a timeout or occasionally as a listing. None of those results mean anything now.
• Mail servers that were never updated. A recipient’s server can still have a SORBS zone in its configuration. Most mail software treats a failed lookup as “not listed”, but a badly configured one may delay or reject mail while it waits on a dead zone.
• Old bounce messages and reports. Security audits, hosting tickets and forum threads copied from before mid-2024 still name SORBS as the reason for a rejection.

None of these is fixed by a delisting request. The first is ignored, the second is the recipient’s configuration to fix, and the third is history.

If a bounce message names SORBS

Read the whole bounce, not just the line that mentions SORBS. Find the server that rejected the message and the date on it. If the bounce is recent and genuinely cites a SORBS zone, the receiving server is still configured to query a service that no longer exists. That is theirs to fix: send the recipient or their mail administrator a short note that SORBS was decommissioned in June 2024 and that the zone should be removed from their filters.

But check whether SORBS was the only reason given. Rejections often cite more than one list, and it is common for the live one — Spamhaus or Barracuda, usually — to be the real cause while the dead one gets the blame. Look up your sending IP and domain on the lists below before you assume the problem is somebody else’s configuration.

If you run the mail server: remove SORBS now

If your own server, spam filter or firewall queries SORBS, take it out. Search your configuration for sorbs and remove every zone you find. The usual places are:

• Postfix: reject_rbl_client entries such as reject_rbl_client dnsbl.sorbs.net in smtpd_recipient_restrictions or smtpd_client_restrictions, then postfix reload.
• Exim: dnslists conditions in your ACLs that include *.sorbs.net zones.
• SpamAssassin and filtering appliances: custom rules or blocklist lists that reference SORBS zones, including any local overrides.
• Firewalls and gateways: any “RBL” or “DNSBL” list configured through a web interface.

Do this even though the zones currently return nothing. A lapsed domain can be registered by someone else, and whoever controls it controls the answers your server gets. A dead blocklist that suddenly answers “listed” for every address would make your server reject all incoming mail. Removing the zone costs nothing and closes that door.

The blocklists that still matter

If mail from your domain is being rejected or landing in spam, these are the lists worth checking. My free blacklist checker looks up an IP or domain against the live ones in one go, and the website blacklist check guide covers the web-reputation side.

List	What it lists	Removal
Spamhaus	Sending IPs and domains	Spamhaus removal steps
Barracuda	Sending IPs	Barracuda delisting
SURBL	Domains that appear in spam	SURBL removal
Cisco Talos	IP and domain reputation	Talos reputation dispute

If you really are being blocklisted

A current listing on a live list means mail that looked like spam came from your IP or mentioned your domain. On the sites I clean, that is usually a hacked website: a PHP mailer script dropped into the uploads folder, a contact form being abused, or stolen SMTP credentials sending through your real mail account. Delisting before that is fixed only buys a few days.

Start with finding out whether your website is sending spam, then removing PHP mailer scripts and checking for stolen SMTP credentials in your mail plugin. Once the source is gone, rebuild SPF, DKIM and DMARC and read getting email delivered again after a hack. If you would rather not dig through mail logs yourself, that is exactly what my malware removal service covers, including the delisting requests afterwards.

Common questions

Is SORBS still active?

No. Proofpoint decommissioned SORBS on June 5, 2024 and emptied all of its blocklist zones. As of September 2026 the sorbs.net domain no longer resolves at all, so no current SORBS listing exists anywhere.

How do I get delisted from SORBS?

You can't, and you don't need to. SORBS no longer exists, so there is no list to be on and no removal process. If mail is still being rejected, check the live lists such as Spamhaus and Barracuda, which are usually the real cause.

Why does my blacklist checker still show SORBS?

Some multi-blacklist tools never removed SORBS from their lookup lists, so they show it as an error, a timeout or a false listing. Ignore any SORBS result. It reflects the checker being out of date, not anything about your IP or domain.

A bounce message says my IP is listed on SORBS. What do I do?

Check the date and the full bounce. If it is recent, the recipient's mail server still queries a dead service and their administrator needs to remove it. Also confirm SORBS was the only reason given, because a live list is often cited alongside it.

What replaced SORBS?

Nothing directly. Mail servers that relied on it generally use other established blocklists instead, such as Spamhaus, Barracuda and SpamCop for sending IPs, and SURBL for domains that appear in spam messages.

More guides: Microsoft Defender SmartScreen, Cisco Talos, SURBL · all blacklist & antivirus guides · full report-link directory.