Friendly Fire in the War on Spam – Part 2: Blacklists

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There are several organizations that maintain blacklists of IP addresses that send out spam. Internet service providers (ISPs) subscribe to these lists to filter out email that comes from these sources. The idea being that this will keep spam from being delivered to their email users. There is no silver bullet for spam and this can be a heavy-handed practice. It works fine when email comes from a private IP address, but what if someone with a large ISP email address, like yahoo.com, starts sending out spam? Should the originating IP address be blocked? This could block every email that comes from a yahoo.com email address. There are plenty of legitimate non-spamming users who have @yahoo.com email addresses. I use yahoo as an example, but this could be applied to any ISP. Most blacklist managers are aware there are large numbers of legitimate users out there and generally do not blacklist larger service providers without good reason. An example of a good reason is when an email service provider shows a total inability to monitor and control spam that originates from their network. This is a real problem for email service providers. Naturally they want customers but at the same time they must monitor and deny service to customers who are spammers. They effectively have to look for customers to turn away. Never the less, no ISP should tolerate spamming in their network. It has serious repercussions on their legitimate users. If an ISP becomes blacklisted, legitimate customers don't get the service they pay for.

Legitimate email users should be aware of this. If your ISP harbors spammers or is soft on spam, there is a chance that your ISPs IP addresses will be added to a blacklist or has been added already. These may well be the same IP addresses that you use to send email. As a result, your email can be labeled as spam, regardless of the content. The best defense is to use an ISP that has a strong anti-spam policy and avoid working with the ISPs on this list.

Get out of there:
You should avoid ISPs that are "spam friendly" or "spam infested." There are plenty of ethical considerations but they should be avoided for tangible reasons. Spam exploited ISPs generally suffer from poor server performance and lost emails. You can also become associated with spammers just by your relative proximity to each other on the internet. This can lead to frustrating returned emails and long sessions arguing with blacklist managers and your ISP to get the common IP address you share with spammers released. The best bet is to avoid these ISPs all together.

Newsletter Problems:
Blacklists can be a major problem for those who send out email newsletters. One of the things many email newsletter management services don't talk about is their delivery rate. Because newsletter services send out so much email their IP addresses are constantly fighting a battle against being blacklisted. Most of the time newsletter services are in the right. It's usually a case of an email behaving like spam or one of their customers making a mistake that trips a flag. This can lead to the newsletter service provider having their IP address blacklisted.

What you need to know is whether or not the IP addresses of your newsletter service provider have been blacklisted. Some services never make any claims to their delivery rate, only how many emails you're allowed to send… with no assurances that your email will ever arrive. One service provider that does speak about this issue is Constant Contact who takes managing the reputation of their IP addresses quite seriously.