The HostKarma blocklist uses spam traps along with other spam detection techniques to identify potential sources of spam.
- Listings occur at the IP level.
- The impact on deliverability is low.
Reasons for getting listed
Your IP address may be listed if:
- You send email to HostKarma spam traps.
- It is not configured correctly with FCrDNS.
- The connection to the receiving server is not closed properly after delivering email.
- Your domain is unfamiliar and along with other signals, may indicate your IP as a spam source.
- Your system was compromised by a third-party to send spam.
- You buy lists or harvest email addresses from websites.
How to get off this blocklist
This blocklist accepts manual requests to remove IP addresses, however, your IP is automatically delisted 5 days after the problem is fixed and no longer detected by HostKarma servers.
Check the status of your IP, fill out and submit the delisting form. Prior to submitting a delisting request, it is recommended to fix the cause of the listing or your request may be ignored.
Tips for staying off this blocklist
- Confirm that your IP has FCrDNS.
- Make sure your servers are properly configured and have no open relays or open proxies.
- Conduct ongoing security checks to prevent unknown third-parties from sending spam.
- Ensure all domains used for sending email or hosting images or websites are configured correctly and not a source for malware.
- Use common top level domains, such as .com, .net, and .org for bulk marketing email.
- Ensure you close the connection to the receiving server using the QUIT command.
- Have a good list hygiene strategy and regularly remove unknown or invalid subscribers.
- Use opt-in consent methods for all subscribers.