How to Fix Cloudflare 521 Error (Port 443 Blocked)
When you see a Cloudflare 521 error, it means Cloudflare’s servers cannot connect to your origin ...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listFix VS Code Terminal Not Opening on Mac
You open VS Code, press Ctrl+` or click the Terminal panel, and nothing happens. The...
Fix Cloudflare Wildcard Subdomain and Root Domain Conflict
If you use a wildcard DNS record (e.g., *.example.com) on Cloudflare, you may run in...
VSCode Python Debugger Breakpoint Not Stopping: Fixes
You set a breakpoint in VSCode, start debugging, and execution passes right through it. The debug...
VSCode Terminal Not Opening After Extension Install: Fix
You install a new extension in Visual Studio Code, restart or reload, and then the terminal panel...
Cloudflare Origin Certificate Troubleshooting Steps
If your website shows SSL errors or users see "This site can’t provide a secure connection,&#...
Topic paths
Quick titles
How to Fix Windows 11 Blue Screen After Update Using Clean BootReact Breakpoints Not Hitting in VS Code? Here's How to FixNginx Upstream Connection Refused: Cloudflare Fix GuideHow to Restore IntelliSense for Dart and Flutter in VSCodeTroubleshoot Locked User Account in RDP ConnectionTroubleshooting VS Code Git Authentication ProblemsHow to Fix Node Sass Build Failed ErrorAvoid sudo pip: Fix Permission Denied in Python