Question 1

How do spam filters work?

Accepted Answer

Modern spam filters use multiple layers to evaluate emails. Rule-based filters check for specific patterns like spam words or formatting issues. Machine learning filters analyze content based on millions of examples. Reputation-based filters evaluate your domain and IP sending history. Engagement-based filters watch how recipients interact with your messages. An email must pass all layers to reach the inbox. Failing any layer increases the chance of spam placement. The filters work together, so problems in one area affect results everywhere.

Question 2

Why do my marketing emails go to spam?

Accepted Answer

The most common reasons are missing authentication, poor sender reputation, or content that triggers filters. First, check that SPF, DKIM, and DMARC are properly configured — this fixes about 80% of issues. Then look at your list quality. High bounce rates or spam complaints damage reputation fast. Finally, review your content for spam trigger words, excessive images, or broken HTML. Low engagement also pushes emails toward spam. If recipients consistently ignore your messages, providers assume they don't want them.

Question 3

Do spam trigger words still matter in 2026?

Accepted Answer

Yes, but context matters more than individual words. Modern filters use machine learning to understand patterns, not just keywords. Using "free" once won't kill your email. But combining multiple trigger words with ALL CAPS, excessive punctuation, and aggressive sales language raises red flags. The safest approach is writing naturally. Avoid hype and desperation. Clear, honest language about real offers performs best. Test subject lines before sending if you're unsure. Focus more on authentication and engagement than obsessing over specific words.

Question 4

Does authentication really affect inbox placement?

Accepted Answer

Absolutely. Authentication is now mandatory for reaching major email providers. Since February 2024, Gmail and Yahoo require SPF, DKIM, and DMARC for bulk senders. Without proper authentication, your emails may be blocked entirely — not just sent to spam. Proper setup fixes roughly 80% of deliverability problems. It proves to email providers that you're a legitimate sender, not someone spoofing your domain. Check your authentication status today. If anything is missing or misconfigured, fix it before sending another campaign.

Question 5

How long does it take to fix deliverability issues?

Accepted Answer

It depends on the problem. Simple fixes like correcting authentication records take effect within hours to a day. Reputation damage takes longer — typically two to four weeks of clean sending to rebuild trust. Blacklist removal varies by list, from 24 hours to several weeks. The key is stopping harmful practices immediately. Continue sending problematic emails and recovery takes even longer. Start with authentication, clean your list, and send only to engaged subscribers. Monitor metrics weekly. Most senders see significant improvement within 30 days of fixing underlying issues.

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