Information about Blacklists

If your computer or domain name have been blacklisted on one or more of the national Spam Blacklist's then you are probably having difficulty sending and receiving email and/or getting to your website.

There are several ways you can get placed onto a spam blacklist but the most common reason is that you or someone on your network has been either infected with a trojan virus or email worm. These infections commonly use your computer and email account to blast out hundreds or even thousands of spam mails a day without your knowledge or consent. Another reason could be that a hacker has compromised your system and is using it as a portal to launch attacks against other corporate networks or websites.

When these things happen your computer or network IP address, or your domain name are placed onto a national blacklist as a measure to stop the attacks. This does not mean that you are assumed to be at fault, it is simply the easiest and fastest way to stop the problem and alert you that there is a problem that needs your attention.

Getting off of a blacklist is as simple as requesting that your IP address or domain name be removed from the list. However, if you continue to be added back onto the list because you failed to clean the infection then each time it will become harder to get cleared off the list. If this continues without resolution your request for removal from the list will eventually be denied until you can provide proof that the problem has been resolved.

Checking to see if you have been blacklisted

Here is how you can check to see if your IP address has been blacklisted:

1. First, find out what your public IP address is by going to http://whatsmyip.org/
2. Your IP address will be displayed at the top of this page, write down the address.
3. Now go to http://mxtoolbox.com/blacklists.aspx
4. Type in your ip address from step 1 into the field marked Server IP:
5. Click on the Blacklist Check button to the right of the Server IP field.
6. Each item in the list is a different blacklist. Each should check out as OK if you are not listed. A red light indicates that your IP shows up on that list.
7. If you have any red lights indicating your IP has been blacklisted then skip to the bottom of this section and follow the instructions under the section marked "To remove your IP address from the list".

Most common email blacklists occur from the email server's IP address and not your local IP address. To check for this the steps are slightly different:

1. First, find out what your mail server IP address is by going to http://www.mxtoolbox.com/index.aspx
2. Type your domain name into the field and click on the MX Lookup button to the right. (example: test@kotter.net in this email address "test" is the Username and "kotter.net" is the Domain Name so I would type kotter.net into the field.)
3. Some domains have more than one IP address for their mail systems. Each address will be displayed to you here. Write down each different address and follow the next steps for each of those in turn.
4. Go to http://mxtoolbox.com/blacklists.aspx
5. Type your mail server ip address from above into the field marked Server IP:
6. Click on the Blacklist Check button to the right of the Server IP field.
7. Scan through the list for any Red marked items. If there are no items marked in red then your mail server is not blacklisted.
8. If any items are marked in red then contact your mail server administrator and alert them to your findings. They will be able to clear the server from the list for you.

To remove your IP address from the list:

1. Click on the blacklist name in the list to be transferred to that blacklist's website.
2. Somewhere on the page you are routed to will be a link to a page where you can submit a request to be removed from the list.
3. Fill out the request and submit it. Your request will be processed ASAP and you should be notified when the removal is complete.
4. Remember to scan your computers and servers for Virus infections, spyware, and check the status of your firewall for protection against intruders, hackers, and pharmers who would use your system as a base of operations for web-based attacks.

Other possibilities

A) If no one in your domain is able to send or receive email and/or your website is not showing up when you try to browse to it then it is probable that your domain name has expired and needs to be renewed. Check with the person who registered your domain name or consult with your IT firm to see if this is the case.

B) If messages sent to you are being bounced back to the sender without being delivered but you are not having problems sending messages out then it is possible that your email account on the server is simply full. Check your mail client to make sure that you are not leaving copies of messages on the server.

Most mail services offer a web-based login page where you can check your mail account over the web. Some mail services have built-in spam folders that will not download to your local system and can eventually fill up your mail account if left unchecked. You should periodically log in and check this folder to clear it out.

If you are unsure about how to check your mail over the internet you should consult with your mail service provider for web links and login information.

C) If you have recently installed any new security software such as a firewall, or Norton Internet Security, etc. then you may need to configure the new software to allow your mail to flow through it. Some firewalls and security programs will block the necessary ports for email or even the email programs themselves until you instruct them to allow the program access to the internet.

Norton Internet Security in particular is notorius for this. If you have installed this recently then you will need to contact your support person to have them take a look at it for you and make the necessary adjustments to the software. If you are computer savvy and wish to attempt it yourself then just open up the settings for the firewall and make allowances for your email program and also for ports 25 and 110. (These are the standard computer ports which all email flow in and out of.)

Last updated on December 3, 2009 by Adam Kotter