Windows 11 Home OEM deactivated after ASRock BIOS update (TPM reset) – 0xC004F200 / 0x803FABBA, no hardware changed

Hello,

My Windows 11 Home was activated and working for over two years. It deactivated immediately after a motherboard BIOS update. No hardware was changed. I have tried every self-service option and cannot reach a human agent, so I'm asking here for help with manual reactivation.

SYSTEM

• Motherboard: ASRock B760 Pro RS (custom-built PC, no key embedded in firmware)
• BIOS updated to version 14.02 (release date 26 June 2026)
• Windows 11 Home, OEM license (OEM:NONSLP channel), key ending in 7MHX6
• Purchased from x-kom (major authorized retailer in Poland) in July 2024. I have the invoice.

WHAT HAPPENED (from Windows Event Logs, 9 October 2026)

• 17:18 - Normal boot, Windows activated
• 18:54:49 - TPM-WMI 1040: pre-attestation health check failed (firmware changed by BIOS flash)
• 18:54:55 - TPM-WMI 519: "The TPM has been cleared. Reason: SRK has changed"
• 18:55:02 - TPM-WMI 1027: TPM ownership taken again
• 18:56:54 - Security-SPP 8198: first activation failure

The BIOS update also updated the Intel Management Engine, which reset Intel PTT (the TPM). This changed the hardware fingerprint, so Windows now treats the same PC as a new device.

ERRORS

• License status: Notification, reason 0xC004F200 (non-genuine)
• slmgr /ato: 0x803FABBA

WHAT I HAVE ALREADY TRIED

• slmgr /ato (fails with 0x803FABBA)
• Activation Troubleshooter (license was not linked to a Microsoft account, so "I changed hardware" has no device to select)
• slui 4 phone activation (no longer available)
• Get Help app: the virtual agent only loops, and "Contact support" redirects to the automated Installation ID validation page, which says "your Installation ID was unable to be validated"
• Verified BIOS settings: UEFI mode, CSM disabled, Intel PTT enabled, Secure Boot on
• No hardware has changed, and Windows was not reinstalled

This is a legitimately purchased license on the same computer. The deactivation was caused only by a firmware update. Could a Microsoft moderator or agent please help reactivate it, or escalate to the activation/licensing team? I can provide the Installation ID, invoice and any other information privately.

Thank you.