Tag Archives: blacklists

How did I get on a Blacklist?

This is the second article in a multi-part introductory series on blacklists and blacklist activity.

At MxToolbox, our experts see the same story play out time and again:

For a few weeks or days, a small number of seemingly random emails bounce back or delivery fails.  At first, this is no real problem; email is never 100%, right?  Then, an important email to a big client goes missing and your users get nervous.  Administrators at your client’s organization says you’ve been blacklisted so they can’t accept email from you.  By then, you realize a large portion of your email isn’t getting through to anyone.  Your business is at risk and it’s all because you are on a blacklist!

Blacklist operators use a number of ways to catch and track undesirable activity but sometimes they capture legitimate businesses, like yours.  Typically, legitimate businesses get placed on a blacklist for one of the following reasons:

  • Relaying spam through in-house email servers
  • Sending malware, viruses or spam from individual accounts
  • Denial of Service (DoS) or other type attacks from malware infected servers or networks
  • Unknowingly Sending phishing emails or unsubscribe attacks
  • Operating a mail server with no reverse DNS, such as from an IP address in your Internet Service Provider’s (ISP’s) dynamic IP address pool (DHCP)
  • Failing to honor unsubscribes when mailing

So, you can see there are a number of reasons that you can end up on a blacklist without actually intending to do something undesirable.  Most often, our experts find that a blacklist issue was caused by your servers passing on spam, viruses or malware.  This condition is highly preventable!

At MxToolbox, our experts understand the common causes of blacklisting.  We can help you take immediate steps to get removed from blacklists and provide thoughtful solutions to keep you off blacklists in the future.  Contact us for more information.

In the next installment of our series on Blacklists, I will discuss some methods for preventing blacklists.

What is a Blacklist?

This is the first article in a multi-part introductory series on blacklists and blacklist activity.

A Realtime Blacklist, or RBL, is a list of IP addresses and domain names that an organization has decided to block, typically for spam.  There are many Blacklists, and each focuses on different types of undesirable behavior.  For example:

  • CBL or Composite Blocking List is a DNS-based blackhole list of suspected e-mail services sending SPAM email resulting from virus or malware infections.
  • Listing on Backscatterer blacklist indicates that your server is issuing “backscatter” in the form of Non-Delivery Reports (bounces) to external users, or misdirected autoresponders and sender callouts.
  • Inclusion in either of the MAILSPIKE Blacklists (BL or Z) means that your IP Address has most likely been identified as being part of a real-time spam outbreak.

Blacklists are typically used to block undesirable internet traffic.  For example:

  • Blocking access to websites on domains known for malware
  • Blocking incoming email from IPs or domains known to be spammers
  • Blocking access to IP addresses based in risky countries

MxToolbox does not own or operate any of these blacklists.  Instead, our email experts curate a list of over 100 blacklists and aggregate blacklist information into a single, central lookup tool.  Our tools enable you to check your mail server IPs and domain names against all these blacklists in a single consolidated interface.  Our monitoring packages enable you to monitor your domains and IP addresses for blacklist activity and get instant notification when placed on a blacklist.  We built our lookup and monitoring tools to help you navigate the complicated world of blacklists.

Your email deliverability depends on staying off of blacklists.  Get protected today.

In our next installment of our series on Blacklists, I will discuss how legitimate businesses sometimes end up on blacklists.

What Blacklists Are and How MxToolBox Helps

Actual MxToolBox Tshirt

One of the most common security challenges for companies is keeping their organization’s email off of Blacklists. When your company gets Blacklisted it will cause major trouble for your business and it will slow down your communication with current customers, prospects and in general the outside world. Email communication is a critical and profit dependent function of any business and this type of communication interruption is both time consuming, costly and completely avoidable.

Most companies discover they have been Blacklisted when they start hearing complaints that their emails have not been received or messages that have been sent are bouncing back. This is really the worst way to find out your company has been Blacklisted because when customers start calling to complain there is already trouble and then you are under pressure to figure out the problem.

A Blacklist, otherwise known as a Real Time Blacklists (RBLs) is a list of problematic IPs that are monitored by Blacklist companies. There are many Blacklist companies and while MxToolBox does provide a Free Blacklist Lookup Tool, we do not control or are affiliated with any Blacklists in any shape or form. Many ISP providers subscribe to Blacklists as an inexpensive means of controlling spam and abusive email senders. There are many reasons a company may end up on a Blacklist, more often that not it’s because a company has not taken appropriate steps to secure their email infrastructure or has been compromised by spammers, hackers, or virus propagators.

Once your IP has been Blacklisted, what can you do?

Well that is where MxToolBox steps in to help. With email service through MxToolBox you won’t have to worry about Blacklists. Our highly trained IT professionals will eliminate your Blacklist problem and we will help you find the root cause of the Blacklist and our service will keep your system secure so the problem will not return.

With our email service your company won’t get Blacklisted and once we have eliminated that worry you can rest assured knowing that if you have any other challenges a real person is only a phone call away. We pride ourselves on our high level of customer service and our ability to solve your email challenges.

If your company has not had your productivity hampered by being Blacklisted then now is the time to sign up for our secure email service. With MxToolBox Email Solutions you can be secure in your knowledge that your email is safe and you won’t suffer the expense of having your email go down at a time when every customer counts.

It is times like these that the ability to cut costs and add productivity makes the most sense. Not only will email hosting by MxToolBox protect you from Blacklists, but it will also keep you safe with world class perimeter protection that will keep you secure from phishing as well as viruses and spam. We offer several levels of Email Hosting Solutions to fit any company and budget and we even offer Zimbra that allows you to access your secure email on any smart phone.

MxToolBox is not affiliated with any Blacklists, we just provide a public tool that can be utilized to see if you are on a Blacklist. If you are on a Blacklist, rest assured as we do offer Blacklist Protection! For more information please feel free to visit our website or email us at info@mxtoolbox.com.

We’re always looking for new Blacklists to add, so if you want to suggest one to us, please send an email to support@mxtoolbox.com.

For information about other Blacklists that have shut down or Blacklists that are having problems, view this forum post.

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