RedHawk SpamHawk Blacklist
The RedHawk SpamHawk blocklist (blacklist) is an IP-based list with low impact on deliverability and a difficult removal process.
Updated on 17 Jun 2026: We updated this guide to add a direct DNSBL check workflow, clarify the limited deliverability impact, and tighten the delisting advice.
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Check if you are listed on RedHawk SpamHawk Blacklist
And 143 other blocklists.
Spamhaus
0Spam
Cisco
NoSolicitado
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abuse.ro
ALPHANET
Anonmails
Ascams
BLOCKEDSERVERS
Calivent Networks
EFnet
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Kempt.net
NordSpam
RV-SOFT Technology
Scientific Spam
Spamikaze
SpamRATS
SPFBL
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Team Cymru
Validity
www.blocklist.de Fail2Ban-Reporting Service
ZapBL
2stepback.dk
Fayntic Services
ORB UK
technoirc.org
TechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftSpamhaus0SpamCiscoNoSolicitadoURIBLabuse.roALPHANETAnonmailsAscamsBLOCKEDSERVERSCalivent NetworksEFnetJustSpamKempt.netNordSpamRV-SOFT TechnologyScientific SpamSpamikazeSpamRATSSPFBLSuomispamSystem 5 HostingTeam CymruValiditywww.blocklist.de Fail2Ban-Reporting ServiceZapBL2stepback.dkFayntic ServicesORB UKtechnoirc.orgTechTheftWhat is the RedHawk SpamHawk blacklist?
The RedHawk SpamHawk blacklist is an IP-based DNS Blocklist (DNSBL) that lists sending IP addresses associated with spam. It operates under the zone name access.redhawk.org. Older public references call the list SpamHawk or SpamHawk RBL, and current blacklist server lists still include the zone name.
Technically, it works through DNS queries. A receiving mail server reverses the sending IPv4 address, appends access.redhawk.org, and checks whether an A record exists. A positive answer means the IP is listed in the blacklist (blocklist). The receiving server then decides whether to reject, tag, or score the message; RedHawk SpamHawk itself does not force a specific SMTP action.
The public footprint points to legacy Sendmail use and self-managed mail servers rather than default use by major mailbox providers. Treat it as a narrow recipient-side filter unless your bounce message names access.redhawk.org or SpamHawk directly.
Who runs the RedHawk SpamHawk blacklist?
There is very little public information available about the organization or individuals behind the RedHawk SpamHawk blacklist. The associated domain, redhawk.org, has the footprint of a personal website rather than a dedicated email security company. Its public content has included recipes and older personal posts, which points to SpamHawk being a personal or small operator project instead of a large commercial blocklist.
How do I get removed from the RedHawk SpamHawk blacklist?
There is no clear public process for requesting delisting from the RedHawk SpamHawk blacklist. Historical discussions point to a former query page at www.redhawk.org/SpamHawk/query.php and no visible removal tool. Current public search results do not show a working delist form.
The practical path is to confirm the exact recipient that rejected the mail, fix the sending issue, and contact the recipient's postmaster or IT team with evidence that the problem has been corrected. If the rejection points only to RedHawk, you still need the recipient to remove or override that local rule because RedHawk does not expose a reliable public removal path.
If you find yourself on any email blacklist or blocklist, fix the underlying issue before chasing removal:
- Review the bounce evidence. Record the SMTP error, recipient domain, sending IP, and any reference to access.redhawk.org, SpamHawk, DNSBL, RBL, blocklist, or blacklist.
- Confirm the listing. Run a direct DNSBL query for the sending IP and compare the result with the rejection message so you do not treat an old monitoring alert as active blocking.
- Secure your systems. Check mail servers, forms, web apps, and any device that sends email for compromise, open relay behavior, malware, or unexpected volume.
- Review sending practices. Use confirmed opt-in, honor unsubscribe requests promptly, remove stale contacts, and avoid sudden volume changes that look like spam.
- Check authentication. Verify SPF, DKIM, and DMARC for every legitimate sending source. Suped's DMARC reporting can help map failing sources to the domain they use, which is useful when a blocklist issue overlaps with authentication failures.
How to check a RedHawk SpamHawk listing
Use a direct DNS lookup when a bounce or monitoring alert names RedHawk SpamHawk. DNSBL lookups reverse the IPv4 address before the zone name, so 192.0.2.99 becomes 99.2.0.192.access.redhawk.org.
Example DNSBL lookupBASH
# Replace 192.0.2.99 with the sending IP from the bounce. dig +short 99.2.0.192.access.redhawk.org A dig +short 99.2.0.192.access.redhawk.org TXT # RFC 5782 test record for an IPv4 DNSBL. dig +short 2.0.0.127.access.redhawk.org A
An A record response in the 127.0.0.0/8 range indicates a listing. A TXT response can explain the listing, if the zone publishes one. If the lookup times out or returns no data, confirm from a second resolver before assuming the zone is inactive.
Do not rely on a generic blacklist checker alone. Some monitoring configurations include access.redhawk.org in long DNS blacklist lists, and a stale alert does not prove that a recipient rejected your mail.
What's the impact of being listed on the RedHawk SpamHawk blacklist?
The impact of a RedHawk SpamHawk listing is usually low. There is no evidence that Gmail, Microsoft Outlook, or Yahoo use this blacklist by default. Public references show usage mainly by organizations or individuals that manually configured mail servers or monitoring systems to query access.redhawk.org.
Historical reports mention OptOnline/Cablevision using SpamHawk as an RBL in 2009, so a listing can still matter when a specific recipient or ISP relies on it. That does not indicate broad modern adoption.
While a listing on this blocklist can block mail to a small set of domains, it is unlikely to cause a widespread deliverability problem. The harder problem is the missing public delisting path, because a listed IP can remain blocked wherever a recipient still trusts that DNSBL.
