My device compute stick H79551-100 probably lost windows 8 OEM key . Is there any way to obtain it and reinstall orginal windows on my device ?

[n_scott_pearson]

If you can still boot into the original image, you can use a tool to extract the key. I use a (freeware) tool from NirSoft called ProduKey.

...S

[DKami2]

​I try to extract key from UEFI using Intel-Integrator-Toolkit without success …. message said "image type x64 is not supported by this ia32 shell"

if i try install clean 32bit image it ask me about key  

[n_scott_pearson]

When it asks for the key, click on the I don't know the key button (or whatever it says). In theory, it should automatically pick up the key (from UEFI) the first time you log into a Microsoft account and then activate the O/S.

...S