After enabling Secure Boot, my Windows 10 computer repeatedly crashes and reboots about every five minutes. The kernel dump reports bugcheck 0x1E (KMODE_EXCEPTION_NOT_HANDLED) with an access violation (0xC0000005). The crashing process is taskhostw.exe, and the stack ends in nt!KiDispatchException, although the dump does not identify a specific third-party driver. Could a Secure Boot certificate or Windows update task be causing this?
1 Answer
Enabling Secure Boot can trigger Windows to update its UEFI Secure Boot certificates. Since taskhostw.exe appears in the crash information, a scheduled certificate or system-maintenance task is a reasonable possibility, but taskhostw.exe itself may only be the process that exposed an underlying driver or firmware problem. In an elevated PowerShell window, check whether the 2023 Windows UEFI CA is present with:
[System.Text.Encoding]::ASCII.GetString((Get-SecureBootUEFI db).bytes) -match 'Windows UEFI CA 2023'
Also install the latest BIOS/UEFI firmware and Windows updates, then review Reliability Monitor and Event Viewer for the crash immediately before each reboot.
I ran that PowerShell command as administrator and it returned True, so the Windows UEFI CA 2023 certificate is already present.