The laptop in question was bought in 2014, with either Win7 or 8.1 (can't remember exactly), then upgraded to 10 when it was first offered as a free upgrade.
Now I want to wipe it and reinstall Windows.
Will I still be able to get 10 again, free?
There should be no problem as the activation is stored on MS servers so it will activate ok if your using a MS account its linked there as well just download the latest win10 Download Windows 10
It always a wise move to create a backup image of the pc with image cloning software
Yes, as Samuria says, your PC's digital licence is stored on the Microsoft activation servers. Just do a clean install of the same edition you had before (Home or Pro) and if asked for a key click 'I don't have one'. It will activate automatically as soon as it can contact the activation servers.
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