How to Fix Nginx Upstream Connection Refused on Port 80
When nginx logs show "upstream connection refused" while connecting to port 80, it means ...
Checklists for software errors, setup, and tool workflows.
1. Reproduce
2. Isolate
3. Apply
4. Verify
Latest checklists
View listFix NET::ERR_CERT_AUTHORITY_INVALID via Chrome Enterprise Policy
If you see NET::ERR_CERT_AUTHORITY_INVALID in Chrome on a managed device, the is...
Fix Chrome Certificate Error Due to Antivirus Interference
You're browsing in Chrome and suddenly see a red warning: Your connection is not priv...
Fix Chrome Certificate Error: Invalid Authority with Proxy Settings
You open Chrome and see NET::ERR_CERT_AUTHORITY_INVALID on every site, even trus...
How to Stop Windows Explorer from Restarting
If Windows Explorer (explorer.exe) keeps restarting—your taskbar disappears and reappears, or you...
VSCode Terminal Not Opening on Ubuntu: Fixes That Work
You open the integrated terminal in VSCode on Ubuntu, but nothing happens—no shell, no error, jus...
Topic paths
Quick titles
How to Fix Docker NGINX 502 Bad GatewayWindows Security App Not Responding? Try These FixesDocker Container Exits Immediately in Docker ComposeMalware Causing Chrome Startup Crash: How to FixDocker Desktop Engine Reset GuideWindows Security App Won't Open AdministratorFix Cloudflare www DNS Not UpdatingWhen to Use --allow-unrelated-histories in Git