🩺 MailMedic

Emails suddenly going to spam: the three usual suspects

When mail that used to land fine starts hitting junk folders — Gmail especially — it's almost always one of these, in this order:

1. Authentication broke (or was never set up)

Google (Feb 2024) and Microsoft (May 2025) now require SPF, DKIM, and DMARC. A missing DMARC record, a second SPF record added by some tool, or an SPF that quietly crossed the 10-DNS-lookup limit — any of these will move you from inbox to spam without warning. This is the most common cause and the fastest to fix.

2. Your list decayed and bounces spiked

Email addresses die at 2–3% per month. Mail a year-old list and 20–30% can bounce — receivers read that as spammer behavior and your domain reputation takes the hit, even for mail to good addresses.

3. Complaints crossed the line

Google's hard limit is a 0.3% spam-complaint rate (aim under 0.1%). Check Google Postmaster Tools — it's free and shows your actual number.

Start with the scan — it separates cause #1 from the others instantly. If you need the fixes and a list clean, the $29 Rescue Kit has both. No subscription; you own the results.