Anubis spam filter overview

The Anubis spam filter uses several types of filters in combination:

• Content-based fingerprinting
• IP-based reputation
• IP-based blocklist
• Malware detection

Infrastructure 

Methodology
All incoming email is scanned, checked for viruses and malware, and given a score based on the likelihood the message is spam. The score determines whether your email is delivered to the recipient, quarantined, or blocked.

Troubleshooting

• Look up your IP reputation at the Mailspike website.
• If your IP address is listed at Spamhaus or SpamCop, go to each website and perform additional lookups to see if you can get further information about the cause.
• Spamhaus
• SpamCop
• Perform a security review of your sending system to ensure it is not being used by an unauthorized third-party to send spam, malware, or phishing email.
• Ensure you are authenticating your email with SPF and DKIM.
• If you feel you have fixed the root cause of the issue, but your IP address is still getting listed, contact Mailspike directly.
  • Be sure to list out all of the steps you took to resolve the issue. Because their resources are limited, you may not get a reply.