Nginx Upstream Connection Refused: Diagnosis and Fixes
When Nginx returns a 502 Bad Gateway or logs "upstream connection refused", it means Ngin...
Software troubleshooting desk
Practical fixes for tool errors, setup blocks, and workflow issues.
Symptom
Cause
Fix route
Verify
Fresh repair notes
All notesHow to Fix Cloudflare 521 Error with Firewall Settings
If you see a 521 Web Server Is Down error when visiting your site through Cloudf...
Fix ERR_CONNECTION_RESET Caused by Chrome Extensions
If you see the ERR_CONNECTION_RESET error in Chrome, it often means a network connection was inte...
How to Recover from a Detached HEAD in Git After a Rebase
You're in the middle of a rebase, you see a message like 'detached HEAD', and you'...
Fix Windows Security App Configuration Error
When you open Windows Security and see a message like "Your IT administrator has limited acce...
Fix Chrome Hardware Acceleration Black Screen on Laptop
If your laptop screen goes black when using Chrome, especially during video playback or scrolling...
Issue queue
SitemapResolve 'Missing Semicolon' in Nginx Config Test
Fix Git Remote Origin Already Exists Error
Fix Nginx Upstream Connection Refused & Upstream Not Found
Fix Explorer.exe Keeps Restarting in Windows 10
Cloudflare 522 Timeout Fix: Increase Server Limits
Docker Container Exits Immediately After Start: Network Fixes
Windows 11 Update Stuck at 0%? Fix BITS Service
Chrome Startup Crash Fix: Disable Extensions
Fix Git Detached HEAD in IntelliJ
Fix 'port already allocated' for Nginx in Docker Compose
ERR_NAME_NOT_RESOLVED Troubleshooting Steps
How to Fix pip Externally Managed Environment Error
Fix Git Remote Origin Already Exists Error
Fix Nginx Upstream Connection Refused & Upstream Not Found
Fix Explorer.exe Keeps Restarting in Windows 10
Cloudflare 522 Timeout Fix: Increase Server Limits
Docker Container Exits Immediately After Start: Network Fixes
Windows 11 Update Stuck at 0%? Fix BITS Service
Chrome Startup Crash Fix: Disable Extensions
Fix Git Detached HEAD in IntelliJ
Fix 'port already allocated' for Nginx in Docker Compose
ERR_NAME_NOT_RESOLVED Troubleshooting Steps
How to Fix pip Externally Managed Environment Error