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Fix Windows Defender Service Not Starting Error - How to Fix Cloudflare Error 525: SSL Handshake Failed-How to Fix ERR_SSL_PROTOCOL_ERROR in Windows 10

2026-06-13 13:29:38office-tools
Fix Windows Defender Service Not Starting Error - How to Fix Cloudflare Error 525: SSL Handshake Failed-How to Fix ERR_SSL_PROTOCOL_ERROR in Windows 10

Final checklist

  • Confirm that the same symptom is gone after a restart or refresh.
  • Keep the smallest working change and undo temporary diagnostic settings.