Disconnect the main battery and the small coin-cell (CMOS) battery. Locate the jumper labeled or PASS on the motherboard.
Note: HP has recently tightened restrictions on this service for older out-of-warranty models, but it remains the safest official method. Method 3: BIOS Password Reset Jumpers hp zbook 15 g5 bios password reset
Plug it into the ZBook, hold , and power it on. Disconnect the main battery and the small coin-cell
If the software methods fail and you cannot provide proof of purchase to HP, the final options are hardware-based. Method 3: BIOS Password Reset Jumpers Plug it
For Enterprise-grade machines like the ZBook, HP provides a service to generate a file. This is a personalized unlock key linked to your specific UUID and Serial Number.
If successful, the BIOS will grant access and allow you to set a new password. Method 2: Contacting HP Support (The Official Route)
Move the jumper cap from its current position to the reset position for 10 seconds. Move it back, reconnect the batteries, and boot up. Method 4: Replacing the BIOS Chip or Motherboard