Downgrading to Windows 8.1 Pro on EliteBook 820 G3

[SnailMiner]

I have a new EliteBook 820 G3, which came with Windows 10 Pro. I need to run Windows 8.1 on it, so I would like to downgrade. Is this possible using the OEM-license that came with the computer? Can it be done with the generic Windows 8.1 image from Microsoft? It asks for the product key which I don't have, so where can I find it? At least I could not find it in the BIOS. Or can the downgrade be done with recovery media from HP?

[Paul_Tikkanen]

Hi:

You would have to buy W8.1 Pro.

You wouldn't be able to use the W10 product key in your notebook's BIOS to activate W8.1.

HP did not offer free downgrades from W10 Pro to W8.1 Pro on that model series.

[SnailMiner]

Hi,

Thank you for the quick reply. I thought the downgrade right in W10 pro versions was a feature of all licenses and not a choice of the manufacturer. I think I remember seeing this model sold with W7 Pro with license based on downgrade rights from W10 Pro, but maybe that doesn't apply to W8.1 Pro.

Manufacturer support is of course another question but most drivers seems to be available for W8.1 from the HP driver download page, suggesting they support it.

[Paul_Tikkanen]

You're very welcome.

I don't know of any PC that offered downgrade rights from W10 Pro to W8.1 Pro or W8.

W10 to W7 yes.  W8.1 to W7 yes.  W7 Pro to XP Pro, yes.  Vista Business to XP Pro yes.

Here is the link to the HP quickspecs for your notebook.  On page 8 you will find the operating systems HP offered.

https://www8.hp.com/h20195/v2/GetPDF.aspx/c04688005.pdf

When downgrade rights are offered, they would have been listed accordingly as on page 5 for the 820 G2 which was the previous model to yours.

https://www8.hp.com/h20195/v2/getpdf.aspx/c04487697.pdf

[SnailMiner]

Hi,

After some phone calls to Microsoft and HP support the downgrade to W8.1 Pro worked out with the OEM license.

First one call to Microsoft referring to this document of theirs:

https://download.microsoft.com/download/6/8/9/68964284-864d-4a6d-aed9-f2c1f8f23e14/downgrade_rights....

The answer was yes, the OEM license includes the right to downgrade. The OEM should take care of media and product key.

Then a call to HP support, which wasn't able to help with either one. Last another call to Microsoft support telling them that HP can't help. MS sent back a generic installation only key, and after installation I could activate the W8.1 Pro installation through phone activation.

So it was possible without buying a new license but not very easy.