Why Your Domain Reputation Dropped Suddenly? 7 Common Causes & Fixes
ScoreSender Engineering•August 7, 2026
1. Sudden Spike in User Spam Complaints
Exceeding Google's recommended 0.10% spam rate threshold triggers automatic domain score penalties.
2. Public DNSBL Blocklist Listing
If your domain or sending IP appears on Spamhaus, Barracuda, or SORBS, mailbox providers immediately flag incoming mail.
3. Broken or Expired DKIM Keys
Key rotation failures result in invalid cryptographic signatures, failing DMARC verification.