what is e-mail blacklisting?

Sample of email bounce back message

Situation:  You've been rolling along in your business, doing good marketing things, including sending out of e-mail newsletters to keep business coming in.  You have an urgent email going to a client, and you are suddenly puzzled when your email message bounces, and you see a message like this:

"spamrats.com - Your server IP address is xx.xx.xxx.xxx and can be found using the lookup tool on the spamrats.com website.  This server has been caught sending spam and is now on this list."

Now nothing you send to your important contact makes it to the recipient - everything you send is bounced back.  What is blacklisting, how did I get on it, and what can I do to fix it?

Q: What is email blacklisting?

A: E-Mail blacklisting is an anti-spam measure, designed as a way for Service and Email hosting Providers to help curb the scourge of unsolicited junk email, otherwise known as spam.  This is one of many different methods employed by service providers to help keep your inbox clean.  The end user demands clean email free from junk and unwanted items, and the blacklisting technique has been around for a long time.   However antispam measures can be so aggressive it can affect you as an e-mail marketer.

Q: What is an email blacklist?

A: Literally, just like it sounds.  It is a listing (in electronic form) that Black List Providers make available to Internet and email Service Providers. It is a list of ip addresses (sometimes domain names) of email servers.   Email servers are the computers which send your email message to the recipient's email server.   Companies like Aol.com and Yahoo.com subscribe to these lists and check every incoming message to see if the server you're sending from is contained in the blacklist.  Smaller mom/pop companies who host with either local or national email service providers may utilize blacklist lookups.  There's no way to know for sure, since it's an internal company process.

Q: How did I get on an Email Blacklist?

A: There are many ways you can wind up on an e-mail blacklist.  Here are some scenarios:
  • You (or someone in your company) is sending out monthly email newsletters in Outlook or Outlook Express, to a large number of recipients - 500 or more per month, and you (or the person sending the email) may not be managing users who want to unsubscribe from your newsletter.  First off, your Internet Service (or mail host provider) may not like you sending out such a large volume of messages, you should use the service of List Mail Service or email marketing Service (more on this later).  Someone who wanted to opt out of your newsletter either (a) did not locate the instructions for opting out of your newsletter and complained to their Internet Service Provider, or (b) requested an opt out and nobody at your company removed their email address, then the customer complained, or (c) you did not provide instructions for opting out of your email newsletter.  Probability: Moderate.
  • You (or one of your email accounts) have an easy to guess email password and unbeknownst to you someone has hacked your account, from your webmail portal and guessed your password.  From their computer they start sending large volumes of email.   Probability: Moderate.
  • A rootkit or remote access trojan has infected your PC, and has turned your PC into a spam zombie.   Scan your PC with several antispyware/antimalware/anti-rootkit/antivirus packages.  Probability: Low, if you keep your PC up to date with updates and security software.
  • Your company has a contact form on the web site, and it has a security vulnerability which is allowing theft of service.  Probability: Low to Moderate.
  • If you use a shared hosting service, in which other businesses share space with your email service, another customer could have send large amounts of email with no opt-out (or for reasons specified in the list above).  In this case the customer (say JaneSmith121@yahoo.com) complained about her emails from them, and Yahoo.com (true story) blacklisted the Server's IP address, which means nobody (including you) can send any email to the entire Yahoo.com domain.   This is the most frustrating problem to deal with, since you have no control over what other companies may be doing with their email service who share space on your sending server.   Probability: Moderate.  Hint: Use a reputable Web Host and Email service provider, you get what you pay for!
  • Someone is spoofing your email address.  What I mean by this is you get a bounce message for a message you didn't send.  This could occur one of several ways - (a) the email account in question was hacked (i.e., someone guessed an email account password).  This commonly occurs with Gmail, Sbcglobal.net, Hotmail, and Yahoo email accounts.  Someone gets one of these spoofed messages, they don't like it and the click "report as spam" button, and some email providers will send your email address to the blacklists. (b) Someone is spoofing through another email server.  Suppose someone hasn't maintained their Email Server and it is vulernable, and someone is sending emails with your email address through another server.  Consider setting up an SPF (Sender Policy Framework) Record in your DNS.  Note this cannot be done with Sbcglobal, Yahoo, Gmail, or other mass mailing accounts. If you're using sbcglobal, att, yahoo, hotmail, yes even Gmail for business use you should consider using your own business email domain name.  This will allow for more control - such as setting up an SPF DNS Records.

The best way to resolve this is approach your Mail Service provider or Internet Service provider, depending if you use your domain name's (say pcnsdfw.com) email server or your Broadband ISP's service provider (AT&T, Verizon, Time Warner, Comcast).   Inform them of the blacklisting and request that they get your Server's IP address delisted from the Blacklist Provider's list.  From personal experience, the larger the company (AT&T, Verizon, Time Warner) the more difficult this can be.   You can approach the blacklist provider and try to get yourself delisted, some may do it, after a time period of three to four weeks, some will do it for a fee.  Backscatterer.org will remove your blacklisting for a stiff fee of $50.

Before using Network Solutions, PC/Network Service used an ultra low cost host provider under another domain name who offered extremely low priced web and email hosting.  The issue with this is there tends to be "hit and run" business.  Somebody signs up with a email and web hosting account, who is sharing with your email server, and in the first 24 hours, they blast out several million spam messages in a short amount of time.  The Web host provider doesn't catch this in time, (or simply doesn't care) and by then the damage is done.  Your host provider's E-mail server is blacklisted, and suddenly you can't correspond with your most important customers.

If you're sending out regular newsletters or email marketing, and your email list is grown to over 500, then it's time to use a List Server or E-Mail marketing service.  These services are designed to send large volumes of email.  Some services will manage the unsubscribe lists for you automatically.  Some will even provide statistical information, including the number of users who are opening your messages.

PCNS has no marketing or referral affiliations with any of these companies.  These solutions are appropriate for small to moderate size business needs.  Businesses wanting to send millions of messages need to look elsewhere.  You should check with your Web hosting provider, as they may have marketing connections with email marketing providers.

Full Service Email Marketing Service Providers

2008 Email Marketing Services Review
Constant Contacts

List Server Service Providers do not have all the features of the email marketing providers above, however they are lower cost and allow large amounts of email messages to be sent.


From the makers of Listserv , the differences between Licensed Software versus Hosted Services.

What is DNS Blacklisting?

Sidebar: How do I know if my domain name or mail server is on a blacklist?

Note: This is technical, and why you should always call your Mail Hosting provider if you suspect you may be blacklisted.  There are two main lookups to perform - a DNS lookup and an IP address lookup.  A DNS lookup is fairly simple (though the results may be somewhat cryptic).  If you know your domain name, simply enter it at the free site MXToolbox.com, and click the button "Blacklists" to see if your DNS Name is on any blacklists.

Note MXToolbox resolves to your incoming mail server's IP address.  Depending on your email service provider, the IP Address of your Sending Email server may be different, and if part of a server farm, the IP address from the sending server may not be the same.   In addition, the ip address of your mail server may be different, depending on if you use a mail client like Outlook (on the PC) or if you use webmail (via Internet Explorer or Firefox).   In any event, you can determine your Service Provider's Sending Email server's ip address by sending an email message to a secondary email account, and examining your email header information by opening the message you just sent yourself from the secondary account.  With this information, perform a Blacklist lookup with this IP Address.