Insert the USB drive into a rear USB 2.0 port on the HP 500B MT. Power on the PC and enter the BIOS setup utility.

You have a couple of options to fix this:

Identify your exact HP SoftPaq number (e.g., SP54668 or similar officially designated for the 500B MT model). Method 1: Flashing via Windows (SoftPaq Utility)

Since there is no mouse support, use your keyboard to move through the menus:

This prompt occurs during POST and stalls the boot sequence.

Because this is a legacy BIOS, your mouse will not work. You must use your keyboard:

He plugged his EEPROM programmer into the motherboard’s header, fired up his old Windows XP laptop, and scrolled through his archives. HP_500B_BIOS_v1.02.bin — Not Found. HP_500B_BIOS_v1.04.bin — Not Found.

Right-click the downloaded .exe file and select .

Writes your configuration to the CMOS memory and reboots.