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Event ID 86: The system was shut down due to a critical thermal event

Windows Event ID Lookup: What Windows event IDs mean: 4625, 4624, 4740, 6008, 41, 7045, 1102 and 3,000 more, with Windows' own message text, the fields and what to check.

Look up a Windows event ID from Event Viewer, a SIEM alert or a log export: what it means, the fields it records, and what to check. Many IDs are used by more than one source (event 41 is both a Kernel-Power crash and a boot error), so every definition is shown, the one people usually mean first. The message text is Windows' own, read from the event providers of Windows 10.0.26200.0, 2026-10-28; the notes are ours, based on Microsoft's security auditing reference.

Try: 4625, 4624, 4740, 6008, 41, 1074, 7045, 1102, 4104, 1149

The system was shut down due to a critical thermal event.

Event 86
Kernel-Power
System log
Error
Message and fields (as Event Viewer shows them)
The system was shut down due to a critical thermal event.             
Shutdown Time = …             
ACPI Thermal Zone = …             
_CRT = …K

Get Plaintext Master Key Array Status

Event 86
Kernel-Boot
System log
Information
Message and fields (as Event Viewer shows them)
Get Plaintext Master Key Array Status

Status: …
SecondaryProtectorVariableName: …
NeedToResealPrimaryProtector: …
NeedToResealSecondaryProtector: …
NeedToResealPca2023Protector: …
SealedBackupEncryptionKeySize: …
SealedPca2023EncryptionKeySize: …
UefiBlobIsCorrupt: …
Pcr7SealingUsed: …
CreationStateVerifiedLocal: …
VerifiedMicrosoftAuthority: …
ContainsAuthorityData: …
BootmgrAuthorityEventCount: …
PrimaryProtectorTargetPcrSealMaskLocal: …
Authority: …

Substatus

PrimaryBlobUnsealStatus: …
BackupBlobUnsealStatus: …
Pca2023ProtectorUnsealStatus: …
BackupBlobValidityCheckStatus: …
BackupBlobStillValid: …
Pca2023ProtectorValidityCheckStatus: …
Pca2023ProtectorStillValid: …
PrimaryBlobResealStatus: …
BackupBlobResealStatus: …
Pca2023ProtectorResealStatus: …
V2ProtectorsUsed: …
LegacyUefiVarQueryStatus: …
LegacyUefiVarCleanupStatus: …
ActivePolicyVersion: …
LatchedPolicyVersion: …
UnlatchedPolicyVersion: …

Validated Unseal Policy

Version: …
VarDataOffset: …
StructureSize: …
PolicyVersion: …
PolicyHashLength: …
WinloadSVN: …
WinresumeSVN: …
BootmgrSVN: …
LKeyPkgId: …