HP Notebook doesn't start with twice caps lock blink

Question

I have a HP Envy 15" noteook, 2014 series, that cannot start. The screen is completely black, and the caps lock led blinks twice. I try to find some info about this blink error code and seems realted to BIOS.

This is what I tried without success:

• Remove all removable devices (wifi, hdd) and power on
• PowerOn with battery only and power supply only
• Remove one of two RAM modules and switch them
• Power ON with WIN+B or WIN+V with a flash drive with recovery BIOS files as suggested here: https://support.hp.com/us-en/document/c02693833
• Remove and replace and also change the CMOS battery

What can I do to revive this notebook?

Solution

I had to try this procedure many times: remove battery for a few seconds, insert battery and power on. At the end Windows could boot up and I update the BIOS using HP installer. Now it is working again.