INBOX.

12 production senders monitored for blocklist + reputation drift. 3 hit Spamhaus SBL within the past 30 days. 1 sending domain has an SPF longer than the 10-lookup limit.

The first sign your domain is on a blocklist is a customer asking why.

MG-007 · transactional.example.com SBL LISTED

Listed 2025-11-04. Open rate dropped from 28% to 4%.

Submit delist request, audit recent sends, isolate compromised IP.