The Blog
Hard-won lessons on email verification, inbox placement, and keeping your sender reputation spotless — from the team that's been verifying email since 2000.
Bounce codes and SMTP errors explained
Discover why your Google Workspace account was suspended after a cold email campaign. Learn how email verification prevents bounces and protects sender.
Read article →
Stop being blocked by Lashback's unsubscribe blacklist. Learn what triggers it, how to check your status, and how to get delisted with actionable steps.
Ensure your email buttons are thumb-friendly. Test tap target size and spacing across mobile email clients to improve click-through rates and reduce user.
Ensure compliance with CASL unsubscribe mechanism requirements in 2026. Learn how to meet the 10-day opt-out window, avoid penalties, and maintain sender.
Understand Mailgun's rate limits and account tiers to avoid delivery failures. Learn how to optimize sending volume, prevent throttling, and maintain.
See how sender reputation checker tools stack up in 2026. Compare accuracy, delivery impact, and real-time insights.
Compare Warmup Inbox vs MailReach pricing, deliverability features, and inbox placement testing.
Ensure your Brazilian email marketing complies with LGPD. Validate consent, check deliverability, and clean your list with precision.
Discover how Bayesian spam filters adapt using recipient feedback. Learn the mechanics, limitations, and how email verification improves training data.
Learn how to ensure your transactional emails land in Gmail’s Primary tab — not Promotions. Reduce bounces, verify your list, and test inbox placement.
Stop being wrongly blacklisted. Learn how to dispute a blocklist false positive with clear steps and proven tactics to restore sender reputation and inbox.
Build a reliable cold email infrastructure with this verified DNS, mailbox, and warm-up checklist.
Stay sharp
Occasional, practical notes on verification and inbox placement. No spam — we'd be embarrassed.
