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Fix Cloudflare Error 521 on Apache Server - Why Chrome Says Extension Permission Denied: Fixes-Resolve Windows Defender Locked File Issue

2026-06-14 11:08:19
Fix Cloudflare Error 521 on Apache Server - Why Chrome Says Extension Permission Denied: Fixes-Resolve Windows Defender Locked File Issue

Result check

  • Keep one change per test run so you know which step helped.
  • Undo temporary changes after the issue is confirmed.