A blacklist, as the name implies, is a list of people or companies who have met with the disapproval of others. In the online world a blacklist refers to those people who have been marked as responsible for generating spam in a very big way. Blacklists are also known as blocklists.
Blacklists are used to combat spam in a very specific way. When spam is reported to one of the relevant spam fighting organizations the IP address the spam originated from is added to a banned or blacklisted IP addresslist. An IP address is the unique location of you or your website on the Internet - think of it as your "home address" online. To put it simply every www.domain.com Internet address has a matching IP address. Any email coming from your website domain also has a corresponding IP address. If your IP address is present on a blacklist then you're potentially wasting your time sending email to customers.
Why are you wasting your time? Modern spam blockers come with the most common blacklists installed and/or allow you to import updated blacklists into your spam blocker. This allows to you block a huge amount of spam but you may also, potentially, block legitimate email. Blacklists are not foolproof.
There are two types of IP address:
Dynamic - changes every time you connect to the Internet. Most commonly used for dialup Internet access. Spammers love these because they're very hard to track and 100% disposable.
Fixed/Static - All websites, most large companies and some individuals use fixed IP addresses. This can cause huge problems if they're reported for pamming.
When an IP address (dynamic or fixed ) is reported for sending spam it's added to a blacklist. There are three different types of blacklists:
Temporary An IP address placed on a temporary blacklist will have email coming from that IP address blocked for several hours. After a few hours the offending IP address is removed from the blacklist.
Permanent When an IP address is added to a permanent blacklist any email server configured to block email from this list will never receive email from that range of IP addresses again.
Comprehensive This is the most damaging of blacklists. Not only does it block a single IP address it also blocks the IP addresses next to it. For example if the IP address 192.156.66.67 was added to a comprehensive blacklist then all IP addresses close to 192.156.66.67 will also be blocked. This can be a huge problem for those website owners using virtual hosting because if your host has ever appeared on a blacklist then you're also on the same blacklist, by default, because of the shared hosting from the same IP range. It's important for all website owners to check whether or not they're on a blacklist. You'll need your IP address (available from your webhost) and you can check your blacklist status at: www.mail-abuse.org/cgi-bin/lookup
Blacklists are a necessary evil due to the volume of spam being sent each day but are not an exact science. Take a few moments from your day and ensure that your website or email address is not being blocked
- Related Videos
- Related Articles
- Ask / Related Q&A




Making Cash With MLM Marketing - What Predetermine,A Favorable Outcome?
By: Dale Dupree | 01/12/2009In this article we'll be taking a look at what determines success in affiliate marketing and how you can achieve achievement for yourself. The causes why most people fail online is because they simply aren't doing things accurately. When people first hear of the possibility of mak
A complete synopsis about MLM scam
By: Scam Ripper | 30/11/2009MLM is a type of business where you employ people to formulate sales and to make returns and then in the procedure you get an income from the people that they sign up that does sales for them.
Types of SPAM and how to avoid or cure it
By: Tim Davis | 28/11/2009Many of you have used auto submitters to advertise your site. Some of you probably made the mistake of using you main email address to submit it with. Some disreputable submission sites will harvest these emails and compile a list of suckers. Your email then is sold on that list to thousands of spammers. Big mistake.
How Do You Remove Spyware From Your Computer - The 2 Best Free Methods
By: Dave Patrick | 08/11/2009Spyware is on most home computers, you would not believe the how it finds it's way into your pc. Don't panic if you have been infected, read the two best methods for removing it free.
Use the right application security for your network
By: Jhoana Cooper | 06/11/2009We all know that the biggest threats for IT systems come from the Internet, computers being attacked with all kind of menaces, all the time. If a laptop or a desktop computer would not be connected to the World Wide Web, the only possible threats would be coming when data from external sources, like CD's, DVD'S, memory sticks or cards etc. would be copied on the systems. So, it is important to choose the right application security for your network and use a powerful internet filter.
The WiFi Security technology
By: Jhoana Cooper | 06/11/2009People use both cable networks and wireless networks, especially in spaces where cables can't be used. In places like historical buildings, campuses, malls, airports etc. it would be really difficult or even forbidden to use cables for Internet access. This is the reason why, in such spaces, using WiFi technology - meaning Wireless Fidelity technology - is the right solution.
SPAM - Facts you need to know!!
By: Ian Kelly | 30/10/2009The amount of SPAM in circulation is increasing exponentially year on year. This fact sheet is designed for those who have a SPAM problem and need to know how to reduce it.
The Trouble With Spam Is....
By: Niall Roche | 20/09/2005 | SpamTo your computer(s) is now a daily chore. The sheer frustration that spam causes combined with the number of lost man hours adds up to junk email being a very real problem.
Are You A Spam Zombie?
By: Niall Roche | 20/09/2005 | SpamTo add a new and extremely worrying phrase to that list - spam zombie. With the net closing in around them spammers are looking for new and more inventive ways to send.
Challenge Response Spam Filters Explained
By: Niall Roche | 20/09/2005 | SpamThat will stop spam forever. For several years now companies have been focusing on faster and smarter software to be installed on your PC or on your servers that will.
Why Your ISP Takes Bribes From Spammers
By: Niall Roche | 20/09/2005 | SpamDay. Yes one single person. ISPs all over the online world have vowed to stop spammers sending such vast amounts of email through their mail servers. Do they.
Spam Control - The Internet Without It?
By: Niall Roche | 20/09/2005 | SpamOf this is the Canspam Act which was passed by the US Senate early in 2004. If you look at what most people used the Internet for you'll find the vast majority of.
Why El Cheapo Domains Will Cost You Money
By: Niall Roche | 18/09/2005 | Online PromotionMean that you should treat it with any less professionalism or seriousness than you do your daytime job. Why? Simply because when you run an online business it's.