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Home / macos-help / Fix Cloudflare Error 521 on Apache Server - Troubleshoot 502 Bad Gateway with Curl Commands-How to Fix Maven HTTP 401 Error for Dependencies

Fix Cloudflare Error 521 on Apache Server - Troubleshoot 502 Bad Gateway with Curl Commands-How to Fix Maven HTTP 401 Error for Dependencies

Updated 2026-06-13 17:41:30macos-help
Fix Cloudflare Error 521 on Apache Server - Troubleshoot 502 Bad Gateway with Curl Commands-How to Fix Maven HTTP 401 Error for Dependencies
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.

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