A dns blacklist or blocklist is a database containing known internet addresses (or IPs)
used by individuals or companies sending spam. Various ISP's and bandwidth providers
subscribe to these DNS blacklist databases to filter out spam sent across their network
or to their subscribers.
Some of the most widely checked DNSBL blacklists (DNS-based lists) are Spamcop,
MAPS blacklist, and SPAMHaus - and CBL.
As a legitimate email marketer, you have to be concerned if your IP addresses are
blacklisted on various dns blacklists and blocklists. If an IP address is blacklisted,
email delivery rates decline as mail servers filter your email. To ensure opt-in emails
are being delivered, it is crucial to monitor your IP addresses and use a CAN-SPAM
compliant email marketing software like
Mass Mailer or our other e-mailing services.
Please use these free relaible blacklist checking sites:
SpamHaus Project Blacklist check.
Spam Cop Blacklist check.
CBL Blacklist lookup.
NJABL Blacklist check.
