Cloudflare 521 Error: How to Check Server Logs - Fix No Network Access on Windows 11 WiFi-Microsoft Edge Sync Troubleshooting Steps

Updated 2026-07-28 16:54:09windows-fixes
Cloudflare 521 Error: How to Check Server Logs - Fix No Network Access on Windows 11 WiFi-Microsoft Edge Sync Troubleshooting Steps
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.