Fix Windows Update Error 0x80070002 with System File Checker - Cloudflare 521 Error: Proxy Misconfiguration Fix-Checklist to Fix npm Permission Denied Errors
Before changing system settings, save your work and note the exact error text so you can compare results after each step.
Extra verification checklist
- Restart the affected app after changing permissions or configuration files.
- Test the same workflow in a clean browser profile or a temporary user account.
- Compare the result on another network if the error may be connection related.