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Email BlacklistingThis article will cover the answers to frequently asked questions related to email blacklisting to help educate and assist SBC customers with dedicated services.
What is blacklisting? Note: SBCIS Dedicated Services does not typically provide email support for dedicated customers that operate their own mail servers and/or hire outside companies to carry/filter their email. Normally, an email server is considered CPE (Customer Premise Equipment). Always check to make sure your Internet access is not interrupted before proceeding with email troubleshooting. Please keep in mind that blacklists are privately run and set their own policies regarding who they block and why. The domain(s) you may be having trouble emailing are choosing to subscribe to these privately run blacklists. If the blacklist in question is unresponsive and will not remove your IP or block, we recommend contacting the destination domain's IT department and politely requesting to be white-listed at their mail server, as they are the domain who is ultimately blocking your email. Many mail administrators are understanding and will work with you or give you recommendations (as long as you are conducting legitimate email communication with their users). Blacklisting is a process of actively monitoring the Internet for reports of email traffic fro a variety of sources sending unsolicited commercial email (SPAM) and then publicly listing that known information on Internet sites for others to reference as a measure to fight SPAM. Many ISP's and independent organizations then use these blacklist databases as a reference filter applied to their inbound mail servers to aid in preventing SPAM and to encourage internet security. How did I get blacklisted?There are many types of lists, but the most prevalent are the open-relay / open proxy lists, and "guilt by association" lists. Open-relay/Proxy server blacklists are based on open ports through which unauthorized network traffic is allowed to flow. The open-relay/proxy lists are the most definite and widely used since they are based on the presumption that a "spammer" found you and likely had relayed a high volume of SPAM through your Message Transfer Agent (MTA), causing your MTA's IP address to be reported to the list by recipients of that SPAM. Many of the better blacklists will run an automated script to verify that the evidence against you is genuine before blacklisting your server. Many blacklists will quickly de-list you if you submit a request to retest your "repaired" mail server. Of course, there will be propagation time after you are de-listed (sometimes as long as a week), because the destination mail server administrators pull the updated lists at times they prefer. Another method blacklist sites use to produce listings is that of "guilt by association". A blacklist site will list much larger blocks of IP addresses than those owned by the suspected abuser. For example, if you are provided with an IP address and the "spammer" owns an address that is close in range to yours and the spammer gets listed on this type of blacklist, your IP block might be listed as well. Usually the reasoning behind this practice is that, by punishing innocent parties, the blacklister is putting more pressure on the ISP to disconnect the suspected spammer's Internet access. SBCIS can only take action against a customer in violation of our AUP and direct evidence must be provided to substantiate the violation (email headers or other evidence of abuse). A blacklist site's evaluation of someone as a "known spammer" or having a "history of spam" is NOT acceptable evidence of violation of our AUP, and does not warrant the termination of service. To view our Dedicated Acceptable Use Policy please visit http://dedicated.sbcis.net, and click on "Policies." How do I know if I am on an e-mail blacklist?The first clue that you may have been blacklisted usually is that you will receive "bounce-back" emails from the destination domain to which you are attempting to deliver mail. *Many of these bounce-backs from destination mail server(s) will inform you of the technical reason that you are being blocked but some will not, depending on the administrator's preferences and type of MTA software. Here are some of the more commonly used blacklist sites. Most provide an automated test that you can run against your IP address:
*Note: Before assuming you are listed on blacklists, make sure to check that your outbound mail server has correct forward and reverse DNS and is not an open-relay, and, make sure other technical settings are correct by referencing your mail server software documentation. How do I get removed from a blacklist?Generally the most expedient way of being removed from a listing is to contact the blacklist directly. Since blacklisting services each have their own procedures for adding and removing IP's, all complaints should be sent directly to the blacklisting service. Please visit the blacklisting services' website for more information. You may also complain to the owner of the domain that is blocking your mail. The administrator of the mail domain made a choice to subscribe to the blacklist and accept its degree of accuracy (which unfortunately is not 100%) in a trade-off for more protection against SPAM. You should be able to find the mail administrator of any domain by visiting the domain's website or doing a WHOIS query with their registrar. Who do I send a complaint to on practices of a blacklisting service?Since each blacklisting service has its own procedures for adding and removing IP's, all complaints should be sent to the blacklisting service and/or the domain that is blocking your mail. Please visit the blacklisting services' website for more information. You may also want to complain to the owner of the domain that is subscribing to the blacklisting service to let them know that the blacklist practices are generating complaints from their users. You should be able to find the mail administrator of any domain by visiting the domain's website or doing a WHOIS query with their registrar. You can find some of the common blacklisting services in the section below on Who are some of the common blacklisting services? How can I avoid being blacklisted in the future?There are several ways to avoid being "blacklisted". MAINTAIN and update your anti-virus software. Your anti-virus software manufacturer should provide helpful information on virus definitions through a "threat list." New threats of viruses are listed on a daily basis, while other viruses are re-coded and re-distributed. Some of these viruses, called worm-viruses, are self-propagating infections that embed themselves into your system files - causing the virus to send out SPAM, without your knowledge, but that appears to come from you (your IP address). MAINTAIN your security features on your PC or Network Servers. Open Mail Relays have become a major cause for blacklisting. An Open Relay is used as a conduit to send UCE/SPAM through your connection by spammers who, thereby, mask their identity and make it appear as if you are the originator of the message. You may find instructions on how to test for, and close, open relays by researching various blacklist and anti-spam resources. DON'T SPAM!!! It is considered a Violation of our Acceptable Use Policies and Guidelines to distribute unsolicited commercial email. Spamming is punishable by blacklisting and termination of service, and has also been outlawed by many states. What are some of the common blacklisting services?The most common of blacklisting services are:
All of the foregoing blacklist services are generally similar in functionality. Some have different procedures in regard to de-listing your IP address. How do I get additional information on blacklisting? Online information is easily found with the following suggested key words.
Prevention Information can be found at:
http://www.ftc.gov/bcp/conline/edcams/infosecurity/resources.html
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