Frequently asked questions

What is the ASN DROP? What is DROP? What is EDROP? Who should use the DROP / EDROP list? Are DROP and EDROP also available via DNS lookups? How often should my system fetch the DROP / EDROP list? Can I use DROP on my Cisco router, or other firewalls, web filters & proxies? Can DROP be used on other operating systems? How do I remove an ASN from ASN DROP? Why am I listed on the ASN DROP? How can I remove a range or ASN from DROP, EDROP or ASNDROP? What are "hijacked netblocks"? What else can ISPs use DROP for? The DROP list is free for any use, how can it be any good?

What is the Botnet Controller List (BCL)? How often is the Botnet Controller List (BCL) updated? How to obtain access to Botnet Controller List (BCL)? Can the BCL block legitimate traffic? In what formats is BCL offered?

What is CSS? Misconfigured SMTP servers (general) Misconfigured Plesk hosts in CSS Misconfigured cPanel in CSS Misconfigured Direct Admin in CSS Why is my IP address listed in CSS? Removing an IP listed in CSS How do I use CSS and what is its return code? (127.0.0.3) Using SpamAssassin and Rspamd with Spamhaus data for CSS How does CSS handle IPv6 addresses?

What is the Domain Blocklist (DBL)? Why is a domain listed in Domain Blocklist (DBL)? All about removing domains from the Domain Blocklist (DBL) Can you scan my site and check that it is secure? Why is a hostname listed in the abused-legit component of the Domain Blocklist? How do I remove myself from the abused-legit component of the Domain Blocklist? Do the "abused legit" or "abused redirector" listings include full URL/URI links? What is the "abused-legit" component of the Domain Blocklist? What do the 127.*.*.* Return Codes mean in DBL? Is the DBL included in the Spamhaus Zen DNSBL? Can the DBL be used to look up IP addresses? Can DBL be used in a Response Policy Zone (RPZ)? Can DBL be used with Microsoft Exchange? Can the DBL be used to filter blog spam? Can wildcard queries be used with the DBL? URL shortening or re-directing services and the DBL Is there any published code available to query the DBL in my application? How can I test the DBL? Using SpamAssassin and Rspamd with Spamhaus data for DBL I am in China. Why is the DBL listing non-spam domains such as twitter.com, facebook.com or pinterest.com?

Misconfigured cPanel What is the eXploits Blocklist (XBL)? Why was my IP listed in the Exploits Blocklist (XBL)? I delisted my IP, but it keeps getting listed again. Why? I get error messages that I'm blocked by XBL, but when I check my IP on your site it's not listed. Why? Misconfigured Plesk hosts in XBL Misconfigured Direct Admin in XBL What do the different return codes in the XBL mean? Should providers use the XBL to block their own users? How often is the XBL zone updated? Can IPs or ranges be nominated for inclusion? Using SpamAssassin and Rspamd with Spamhaus data for XBL How does XBL handle IPv6 addresses? How do I keep my computer from getting infected by malware? How do I find the bot on my network? What is a NAT Firewall, Router, or Gateway? TOR and VPNs in XBL What is a sinkhole IP? I'm running Linux (FreeBSD, OpenBSD, UNIX...) and cannot be infected with a virus. Right?

What is a botnet command and controller (C&C)? What is a blocklist? What is an Internet Protocol (IP) address What is a domain name? What is an Initial Access Broker? What is a top-level domain (TLD)?

IP listed in CSS - General help Misconfigured SMTP servers Misconfigured Plesk Hosts WiFi and Home Networks Closing Port 25: General Advice Hacked Website or CMS - General Information CMS-Specific help How can packet sniffing help find the problem?

What is the HBL? What is the purpose of the HBL Why am I listed on the Hash Blocklist (HBL)? How do I remove myself from the Hash Blocklist (HBL)? How do I use the Spamhaus HBL? How do I obtain access to the HBL? Using SpamAssassin and Rspamd with Spamhaus data for HBL

How do I control affiliate spammers? What is "confirmed opt-in" (COI)? What to do about older, stale email lists (which are not purchased) but that have not been well maintained? What happens to contact lists when two companies merge, or a company is acquired? What is the Spamhaus policy regarding E-pending (Email-appending)? Regarding listwashing, waterfalling, and verification services Recommended reading for any email marketing company Misconfigured SMTP servers What about purchased or rented lists?

How do I control affiliate spammers? What is considered marketing or bulk email? What is the right way to send marketing e-mail? How not to do what spammers do... Email authentication How can we improve deliverability? How should I handle unsubscribe requests? How should I handle spam complaints?

What is the Policy Blocklist (PBL)? Help! My IP address is on the Policy Blocklist (PBL)! Enabling SMTP Authentication Why is Port 25 for email transmission no longer widely supported? What IPs should be removed from the Policy Blocklist (PBL)? Single IP removal for outbound email server administrators Why can freemail addresses not be used to request removals? What if I want to run a mail server on IPs listed in the Policy Blocklist (PBL)? Who is eligible for an ISP PBL Account? What is the "Primary Domain" for ISP Accounts? Instructions for creating and setting up an ISP PBL Account Confirmation code missing or password reset "PBL Zone Listing" vs. "Master Range" - What is the difference? How does an ISP add or remove IP ranges from the PBL? "[CIDR range] conflicts with other PBL master records." What does this error mean? Does the PBL only contain dynamic IP ranges? How do I remove a Spamhaus-created PBL Zone Listing from my ISP Account? How to correctly use the PBL Avoid common errors: how the PBL should not be used What zone should my server or spam filter query for PBL? Should an ISP use the PBL to block its own users? Should I use the PBL to block access to my webserver? How often is the PBL zone updated? Using SpamAssassin and Rspamd with Spamhaus data for PBL Can I nominate IP addresses or ranges for inclusion?

What is the Spamhaus Blocklist (SBL)? Listing Criteria for inclusion in the Spamhaus Blocklist (SBL) Is my IP listed in Spamhaus Blocklist (SBL)? How do I get an IP removed from the Spamhaus Blocklist (SBL)? Can I remove my IP from the Spamhaus Blocklist (SBL) if I am the end-user? Is there any fee for Spamhaus Blocklist (SBL) removal? When will my IP be removed from the Spamhaus Blocklist (SBL)? I am a system administrator. How can remove my IP(s) from the SBL? How do I use the SBL? What zone should my server or spam filter query? How often is the SBL zone updated? How does Spamhaus SBL organize network names? Using SBL to block Apache websites Can the SBL can also block domains? What is "URIBL_SBL"? Using SpamAssassin and Rspamd with Spamhaus data for SBL

What is the Zero Reputation Domain Blocklist (ZRD)? Why is a domain listed in Zero Reputation Domain Blocklist (ZRD)? How do I remove myself from the Zero Reputation Domain Blocklist (ZRD)?