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Fixing ERR_SSL_PROTOCOL_ERROR Certificate Issues - Fix Chrome ERR_TUNNEL_CONNECTION_FAILED Caused by Antivirus-Microsoft Store Error 404: Quick Fix Guide

2026-06-14 03:20:28developer-tools
Fixing ERR_SSL_PROTOCOL_ERROR Certificate Issues - Fix Chrome ERR_TUNNEL_CONNECTION_FAILED Caused by Antivirus-Microsoft Store Error 404: Quick Fix Guide

Final checklist

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