how can I get back my windows licence key

[Murat1]

how can I get back my windows licence key

[Paul_Tikkanen]

Hi:

You never lost it.

The W8.1 product key is in the BIOS, and if you need to reinstall W10, you don't need to know the product key.

You can reinstall W10 for free as follows...

You can make a W10 USB flash drive installer with the Microsoft Media Creation Tool, using an 8 GB flash drive using another Windows PC, if your PC is not working.

https://www.microsoft.com/en-us/software-download/windows10

If you are asked to enter a product key during the installation process, select the 'I don't have a product key' option, and W10 will install and automatically activate once you are connected to the internet.

Here are the steps to create the W10 USB flash drive installer...

Select Download tool now, and select Run.

If you agree to the license terms, select Accept.

On the What do you want to do? page, select Create installation media for another PC, and then select Next.

Select the language, edition, and architecture (64-bit or 32-bit) for Windows 10. You want 64 bit.

Select which media you want to use:

USB flash drive. Plug in a blank USB flash drive with at least 8GB of space. Any content on the flash drive will be deleted.

Then you can install the drivers and available software from the PC's support page...

https://support.hp.com/us-en/drivers/selfservice/hp-elitebook-820-g1-notebook-pc/5405376

If you want to see the Windows product key in the BIOS, I have zipped up and attached a free utility below that will show you the W8.1 product key in your notebook's BIOS after you reinstall W10.