Windows 10 activation key

Hi. My Windows key is Retail, according to the results I get from typing "slmgr.vbs /dlv " in CMD. However, someone told me I can't transfer the key, even if it's Retail, if Windows was pre-installed. In fact, Windows 10 was pre-installed and ready to use when I bought the laptop. According to...

So when I install an SSD (without Windows 10 installed) on a computer that previously had an HDD (with Windows 10), and when installing the new SSD to the computer and then plugging a USB with a Windows 10 installer, is it necessary to buy another activation code for Windows or does it keep that...

I have a PC that was built a while ago for me by a friend, and they used an Ebay windows key. It's finally been deactivated by Microsoft, and I just wanted to ensure that using a new (real) licence key on it will just change it to activated again, without removing any personal...

This is pretty ridiculous in my opinion. I have my perfectly working (before I wiped my hard drive and did a fresh install) Windows 10 product key. Tried to enter it twice thinking I made a mistake, and it wouldn't work. So I called Microsoft and apparently because it was part of the "free...