An IP noticeably sending spams is listed on blacklists. These blacklists protect email users from potentially harmful spams sent to their inbox from IP addresses displaying suspicious activity.
Reasons for IP address being blacklisted:
- Outgoing Spam emails
- Virus activity or outbound attacks
- Infected website running from the IP address
- Malicious activity
Blacklisting an IP address by a blacklist center blocks the mail traffic at all the Email servers using spam protection from same blacklist center.
How can I confirm if my IP address is blacklisted?
You can verify the IP address status using the following sites:
The result displayed will convey the IP address status as blacklisted specifying the name of the blacklist centre and Ok if not blacklisted.
Clicking on the details will display the link of the blacklist center, which will help you to find out the reason for IP blacklist. Post gathering the details, you need to make sure you take the necessary actions before sending the delist request. If you send the delist request without acting appropriately than it might result in permanent blacklisting of your IP.
Following measures should be taken before sending the delist request:
- Examine the outgoing spamming from the server and act accordingly. You can change the password or set a complex and strong password for the compromised email id. In addition, you need to check the device on which the id is configured and clear the queue. Wait for a couple of days to check if the spamming does not occur again before you move to IP delisting.
- Before sending the delist request verify if the PTR record of an IP address is set and SPF record of the domain is set.
- For an IP address blacklisted due to outbound attacks on different servers, scan the server and eliminate all malicious files once the attack has stopped. Later, you can send the delist request.
- For an IP address blacklisted due to infected website attacks like phishing, clear the infected pages and patch the site. Once the vulnerability is detached you may send the delist request.
Post-acting against the reported issue monitor the server for a few days and if no spamming or suspicious activity found they you can begin the IP delist procedure.
IP delisting procedure:
Post verifying there is no suspicious activity you can proceed to the IP delisting procedure. For spamming make sure, before the delisting request is sent PTR and SPF records are set. Different blacklist centers have different delisting procedures, the centers like CBL, Spamhaus provide free of cost delisting while some other centers automatically delist the IP address after a specific time frame providing express delisting which is on the chartable basis.
(Note: – Please make sure that the IP delisting can be sent only by IP owner in our case we can send the delisting request on behalf of our client)
Below given are a few examples of the delisting process depending on the service provider.
1. Outlook/Hotmail Delisting: For an IP blacklisted by Hotmail/ Outlook, a bounce-back message will be received if you send an email to the user with this provider stating your IP address is in a blacklist. In this case, post all the required measures are taken you can join SNDS program and authorize it. If you join the program, you will be provided with the portal displaying the details regarding the traffic received by Hotmail and Outlook from your IP address. Take the necessary actions and send a delist request by filling up the form. Hotmail will respond to the mention email id after completing their procedure stating whether the IP is delisted or not.
2. CBL/ Spamhaus: – If an IP is blacklisted in CBL due to suspicious activity, it is listed in Spamhaus by default. In addition, Spamhaus can list IP separately for a variety of reasons. Detailed information on the suspicious activity will be delivered to you. Take the necessary action and then send the delist request to CBL and Spamhaus respectively. Please note that for an IP address blocked by CBL, emails sent to Outlook.com will not be delivered.