Do not turn off your computer during the flash process. A failure here can damage the motherboard. Troubleshooting & Alternatives If HPQFlash Fails
Go to the HP Customer Support - Software and Driver Downloads page.
HPQFlash.exe -s -b "C:\Drivers\BIOS\68SCF.CAB"
If you require HPQFlash for a legacy deployment, it is safest to download the from the official HP Business Support site and extract the utility from there. Use the -s switch for silent deployments and always ensure AC power is connected.