This blocklist is no longer operational. DNS queries return NXDOMAIN. Remove from MTA configurations to avoid query timeouts.
What it is
DRMX was a small independently operated DNSBL. The project has been discontinued and its DNS infrastructure is no longer operational.
How it affects SMTP delivery
No impact. Remove from configurations.
What causes a listing
N/A, defunct.
How to get removed
No removal necessary.
For the full reference catalog, see the email blocklist directory.
Delisting process in detail
The DrMX blocklist targets observed spam sources. Delisting is handled through the operator’s portal. Response times are typically within 24-72 hours for well-documented requests. Automatic decay applies when the observed spam pattern stops, usually within 7-14 days. DrMX is a specialty blocklist with focused coverage rather than global deployment.
Prevention practices
DrMX prevention follows standard anti-abuse fundamentals: authenticated sending, list hygiene, complaint monitoring. Because DrMX is a smaller blocklist, its impact is limited to receivers that specifically query it. Monitor DrMX alongside major public blocklists (Spamhaus, Barracuda) for comprehensive coverage. Gradual IP warmup, confirmed opt-in, and prompt bounce suppression are the primary defenses.
Common listing causes
DrMX listings correlate with observed spam patterns from the listed IP. Common causes include purchased lists that hit DrMX honeypots, compromised shared-hosting accounts, and volume spikes without proper warmup. Because DrMX operates a smaller network than major blocklists, listings typically reflect specific abuse rather than broad reputation issues.
Related blocklists
DrMX operates alongside other specialty blocklists in the broader anti-spam ecosystem. Enterprise reputation monitoring combines DrMX with major blocklists (Spamhaus, Barracuda, SpamCop) for comprehensive coverage. Smaller blocklists sometimes provide early-warning signals for patterns that eventually appear on broader consensus lists.
About the Author
Alaa · LinkedIn
Email infrastructure specialist with 8+ years of hands-on experience in SMTP, deliverability, and email verification. I’ve configured and troubleshot mail systems across Postfix, Exchange, and cloud relays, managed IP reputation and warmup campaigns, and built verification pipelines processing millions of addresses. My work spans DNS authentication (SPF, DKIM, DMARC, BIMI), bounce handling, blocklist monitoring, and compliance frameworks including CAN-SPAM and GDPR. I write every article on SMTPedia to give email professionals, developers, and marketers the accurate, RFC-grounded reference they need.
About SMTPedia
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