# Knowledge Base

Explore deliverability and learn how to fix spam, send email to right folder

## Articles

### [How to Do a Gmail Blacklist Check (And Get Off It)](https://folderly.com/blog/gmail-blacklist-check)  
*Time to Read: 15 min*  
Learn how to run a Gmail blacklist check, spot early warning signs, and follow clear steps to get delisted and restore your sender reputation.

### [How Gmail's Gemini AI Changes Email Deliverability in 2026](https://folderly.com/blog/gmail-gemini-ai-email-deliverability-2026)  
*Time to Read: 12 min*  
Gmail's Gemini AI is fundamentally changing email deliverability. Learn how AI summaries affect your metrics, why content quality is now a deliverability signal, and what you need to do differently in 2026.

### [Folderly vs Instantly.ai: Why Cold Email Success Requires More Than Campaign Management](https://folderly.com/blog/folderly-vs-instantly-cold-email-deliverability)  
*Time to Read: 6 min*  
Instantly.ai manages cold email campaigns efficiently, but can't tell you where emails actually land. Here's why successful cold email operations use both platforms - and what each one does best.

### [Why Halloween Should Be an Official Holiday for Everyone Who Got Ghosted in the Spam Folder](https://folderly.com/blog/halloween-official-holiday-of-spam-folder)  
*Time to Read: 5 min*  
If you've ever watched your perfectly crafted cold email vanish into spam, you deserve a day off. Here's why Halloween should be an official holiday for email senders everywhere.

### ["Just Send 15 Emails a Day"? Why That Advice Is Killing Your Deliverability](https://folderly.com/blog/why-send-15-emails-kill-your-deliverability)  
*Time to Read: 3 min*  
If you’ve been told to limit your sending volume to 15-30 emails per day, that’s not safety - that’s stagnation. Learn how Folderly grows sender reputation so you can scale safely.

### [Why We Invested Over $5 Million In Our Technology and Why Folderly Is the Only Real Deliverability Solution That Works](https://folderly.com/blog/why-folderly-is-the-only-real-deliverability-solution)  
*Time to Read: 3 min*  
Most deliverability tools simulate results instead of creating them. Learn why Folderly's proprietary AI-driven infrastructure is the only solution that actually fixes your sender reputation - permanently.

### [Google Postmaster Tools v1 Is Retiring: Here's Everything You Need to Know About the v2 Update](https://folderly.com/blog/google-postmaster-tools-v2-migration-guide-2025)  
*Time to Read: 5 min*  
Google is retiring Postmaster Tools v1 by end of 2025, removing domain and IP reputation dashboards. Learn what's changing in v2, why it matters, and how to prepare your deliverability monitoring.

### [What Does Bounced Email Mean? Complete Guide to Email Bounce Fixes](https://folderly.com/blog/email-bounce-complete-guide-fixing-preventing-bounced-emails)  
*Time to Read: 7 min*  
Stop losing leads to bounced emails. Learn what causes email bounces, how to fix them, and proven strategies to protect your sender reputation and boost deliverability.

### [Email Spam Words to Avoid in 2025: Complete Guide + Safer Alternatives](https://folderly.com/blog/email-spam-words-to-avoid-2025-complete-guide-alternatives)  
*Time to Read: 6 min*  
Stop letting spam trigger words kill your email deliverability. Discover 100+ words that land emails in spam folders and get proven alternatives that actually work in 2025.

### [My Deliverability Is Fine, But Where Are the Replies? (The Missing Piece in Email Outreach)](https://folderly.com/blog/deliverability-vs-replies-email-outreach-guide)  
*Time to Read: 5 min*  
Getting perfect deliverability scores but no replies? Learn why inbox placement is just the beginning and discover the proven framework for turning email visibility into actual conversations and revenue.

### [Why Are My Cold Emails Going to Spam? (Complete 2025 Fix Guide)](https://folderly.com/blog/why-are-my-cold-emails-going-to-spam-2025-fix-guide)  
*Time to Read: 8 min*  
Discover why cold emails often land in spam and learn the complete 2025 guide to fix it. This article covers essential email authentication (SPF, DKIM, DMARC), sender reputation management, content best practices, list hygiene, sending patterns, and a 7-step remediation plan to improve inbox placement and email outreach success in 2025.