Windows 10: Can I use license key from old laptop, even if its "OA" ?

I have a broken old laptop.
However, it does have one useful thing: a Win7 license key.
Can I use this key to install Win7 on a desktop and upgrade to Win10?

The laptop authenticity sticker on the underside says its "Home Premium OA" and OA I think means its already activated. So I wonder if I have to "deactivate" it first before activating again?

:)

 

Windows 10 Product Key

If Windows 8 preinstalled on that laptop, the answer is no; if Windows 8 was a store bought license yes.

Learn more:

How to Transfer your Windows 10 License to a
New Computer

 

Redeem my Windows 10 upgrade from Windows 7 product keys

If the license is Retail yes, if its OEM no.

 

I don't think so. OA I believe simply means it is a factory OEM (Original Equipment Manufacturer) installation and that means the license key is only valid for that PC. If you attempt to use it then you will just get a failure notice as the key is already in use.

 

Strictly no but Windows 10 is amazingly lenient about such things. Worth a try.

 

I just read somewhere that I have to deactivate a Windows license key, and only then can I re-use it.
slmgr /upk [your-windows-key]

How To Uninstall Your Windows Product Key Before You Sell Your PC

 

Doesn't apply to OEM as you can't reuse it anyway and in any case if the laptop is broken you'll not be able to do it.

You could try installing 10 and entering your 7 key (you don't have to install 7 and upgrade). It will either work or not. If it doesn't work you could try telephone activation, tell them it is only installed on one computer and see what they say. As @cereberus said according to the license you can't do this but there is nothing wrong with trying.

 

OA simply means it's an OEM Activated Product Key. From Win7 back, most times a Key from one brand was prohibited from installing on a different brand, especially when using a CD for installing. As mentioned, Win10 changes things.

 

Pure myth. slmgr /upk only removes the product key from the local computer. It has absolutely no affect on the activation or digital license stored on Microsoft Activation Servers.

 

Bingo. Exactly.

 

Factory Windows 7 OEM installs use a Generic OEM key. Dell has their keys, Acer theirs, etc. As an example every Dell with Windows 7 Home Premium will have the same Dell key. Those PC's don't activate online, they activate against a SLIC table in the BIOS. Use a Dell OEM disk on an Acer and the SLIC table won't match, no activation. No SLIC table means no activation too. Those generic OEM keys are also blocked from online activation. Windows 10 won't activate with them either. That being said, that generic OEM key is not the key printed on the COA sticker. That key is unique and its there for use with stock Windows 7 install media. I've had to do a phone activation when using them though. According to the EULA, OEM keys/installs are not transferable.