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Real email senders sharing what nobody told them.
'Delivered' doesn't mean 'inbox.' I was celebrating 99% delivery while sitting in spam.
Ran a seed test for the first time. 35% of my Gmail subscribers were seeing me in spam. The dashboard still said 99% delivered.
My company changed ESPs and nobody warmed up the new IP. We went straight to spam for a month.
Migration meeting had zero mention of warming. IT changed the DNS records on Friday. Marketing sent Monday's newsletter to 150K people from a brand-new IP. Inbox placement: 23%.
Buying a list doesn't just hurt you once. Those spam traps follow you.
Purchased a 'verified' list in 2021. Still finding trap hits from those addresses in 2024. They got merged into segments, copied to other lists, and contaminated everything.
DMARC was set to p=none for three years. I thought that meant it was working.
A client asked me about our DMARC policy during a vendor security review. I said 'yes, we have DMARC.' They asked what our policy was. I didn't know p=none means 'do nothing.'
One bad send can tank a domain reputation that took months to build.
Sent a re-engagement campaign to 40K inactive subscribers. Bounce rate spiked, complaints spiked, and Google throttled us for three weeks. Three months of good sending, gone in one afternoon.
SPF has a 10 DNS lookup limit. I had 14. Nobody told me for two years.
A freelancer audited my DNS and asked why my SPF was broken. Two years of failed authentication and not a single alert from my ESP.
Your domain reputation matters more than your IP reputation now. Changing ESPs doesn't reset your history.
Switched ESPs thinking it would fix our spam folder problem. Same domain, same reputation, same spam folder. The problem followed us because it was never about the IP.
The 'deliverability' tab in my ESP shows nothing about actual deliverability.
Asked support what 'deliverability rate' meant. Long pause. 'It's the percentage of emails we successfully handed off to the receiving server.' That's delivery, not deliverability.
Email warmup tools that use fake engagement are pointless. Real warmup means real subscribers.
Spent $200/month on a warmup tool for three months. When I turned it off and sent a real campaign, my inbox placement was exactly the same as before. The fake opens meant nothing.
Soft bounces don't clear themselves. I had addresses soft-bouncing for 8 months.
Exported my full list and filtered by bounce history. 1,200 addresses had been soft-bouncing every single send for months. Still marked 'active.'
Heavy HTML emails render worse AND hurt deliverability. Nobody mentioned that.
Sent a plain-text version of our newsletter as a test. Open rate jumped 12%. Click rate jumped 8%. Turns out half our subscribers' clients were clipping the HTML version.
Sunset policies aren't optional. Mailbox providers watch whether you remove inactive subscribers.
Google Postmaster Tools showed our domain reputation dropping from High to Medium. The only change was we hadn't cleaned inactives in 10 months. Removed 25K inactive addresses. Reputation recovered in two weeks.
My ESP was throttling me because my list was too small to matter.
Switched to a smaller ESP and my deliverability improved overnight. Turns out the big provider shared IPs between hundreds of senders and my 8K list got the worst ones.
Double opt-in isn't just 'nice to have.' It's the only way to prove consent and catch typos before they become problems.
Single opt-in form collected 3,000 signups at a conference. 400 were typos. 12 were spam traps. Found out when we got blocklisted two weeks later.
Feedback loops exist. My ESP never told me I was getting spam complaints.
Read an article about Yahoo FBLs and realized my ESP had been quietly suppressing complainers without ever showing me the data. My complaint rate was 0.4% and I had no idea.