Fix Nginx Upstream Connection Refused in Proxy Pass
When Nginx returns a 502 Bad Gateway or logs upstream connection refused
Software troubleshooting desk
Practical fixes for tool errors, setup blocks, and workflow issues.
Symptom
Cause
Fix route
Verify
Fresh repair notes
All notesHow to Push a Git Detached HEAD to Remote
You're working on a Git repository and realize you're in a 'detached HEAD' state....
Taskbar Icons Missing But Taskbar Visible: Fixes
You see the taskbar at the bottom of your screen, but the icons—like the Start button, search bar...
Fix Cloudflare Origin Certificate Mismatch Errors
If you see 'Origin Certificate Mismatch' in Cloudflare or browser warnings, it usually me...
Fix net::ERR_CERT_AUTHORITY_INVALID on Chrome in Linux Terminal
When you see net::ERR_CERT_AUTHORITY_INVALID in Chrome on Linux, it usually means th...
Fix Cloudflare Wildcard Subdomain Not Working
If you've set up a wildcard DNS record in Cloudflare (e.g., *.example.com) but s...
Issue queue
SitemapHow to Fix Bluetooth After Windows 11 Update
Cloudflare DNS Propagation Checker Guide
Linux npm EACCES Error: Practical Fixes
Firefox Secure Connection Failed: Practical Fixes
How to Fix Chrome Crashing at Launch with Registry
Git Lock File Not Deleted: Quick Fix Guide
Resolve Chrome Error Code 0xc0000022 on Windows
Resolve Node Engine Not Satisfied Error
Fix Cloudflare 522 Error from Plugin Conflicts
How to Fix pip Permission Denied macOS
Fix Git Detached HEAD Without Losing Work
Chrome Status Access Violation Fix: Clean Install Steps
Cloudflare DNS Propagation Checker Guide
Linux npm EACCES Error: Practical Fixes
Firefox Secure Connection Failed: Practical Fixes
How to Fix Chrome Crashing at Launch with Registry
Git Lock File Not Deleted: Quick Fix Guide
Resolve Chrome Error Code 0xc0000022 on Windows
Resolve Node Engine Not Satisfied Error
Fix Cloudflare 522 Error from Plugin Conflicts
How to Fix pip Permission Denied macOS
Fix Git Detached HEAD Without Losing Work
Chrome Status Access Violation Fix: Clean Install Steps