I have an HP Envy 13 laptop that originally came with Windows preinstalled, but once I got it, I wiped everything and installed Ubuntu instead. Now, I'm looking to use Windows on the same machine again. Is there a way I can recover the Windows key from it? Also, if that's not possible, I'm trying to run some remote online test software that's only compatible with Windows. Is there an easy way to run that software within Ubuntu instead?
2 Answers
Another possibility is that the Windows key is stored directly in your laptop's BIOS. You won't be able to see it until you install Windows, though. Also, if you previously logged into Windows, the key might be associated with your Microsoft account. Just check if that's the case; if not, you might be out of luck on recovering that key.
You actually don't have to worry too much about recovering the key! Windows often comes with a digital license that's linked to your hardware. When you do a clean install of Windows on that laptop—just make sure to install the same version you had before—it should activate automatically without needing to enter a key. If it prompts you for a key, just skip that step.
But why not consider using WSL (Windows Subsystem for Linux)? It's a great way to run Linux within Windows without needing to dual boot.

Related Questions
Can't Load PhpMyadmin On After Server Update
Redirect www to non-www in Apache Conf
How To Check If Your SSL Cert Is SHA 1
Windows TrackPad Gestures