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Windows Defender Not Opening on Windows 11: How to Fix - Troubleshoot Windows Update Certificate Error After Changing Clock-How to Fix Windows Defender Scan Stuck at 85% or 99%

2026-06-13 13:47:23
Windows Defender Not Opening on Windows 11: How to Fix - Troubleshoot Windows Update Certificate Error After Changing Clock-How to Fix Windows Defender Scan Stuck at 85% or 99%

Result check

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