| From: Stewart Russell via talk <talk@gtalug.org> [I started this message days ago. I delayed, hoping to do some more research. I'm just too busy so I'm sending it without completing it] | If the file /sys/firmware/acpi/tables/MSDM exists (it's read-only to root), | there's probably a key embedded in there you can pull out with strings I knew it was in there somewhere, but I didn't know where. Over the years, Microsoft has changed how they distributed OEM keys. For a long time, it was on a fancy sticker on the computer itself (holograms etc.). There were separate stickers for other bundled MS products like MS Works and MS Office. (I had a system where the sticker was in a little pull-out tray.) Eventually, they put the Windows product key in the "BIOS" (firmware). For a while, I think that they still put the sticker on the box. Datapoints: - my 2013 desktop came with Windows (8.0?) has the embedded key - my 2020 Precision 3440 SFF came with Ubuntu (no Windows license) and does not have that file - my Dell Inspiron 530 (BIOS date 2009; Core 2 Duo E6550) came bundled with Windows and doesn't have that file, at least under CentOS 6. - Chris Johnson's Dell laptop came bundled with Windows but does not have the embedded key. I assume that the file is missing. Unknown: the vintage of the laptop Unknown: There was a limited time where you could update pre Win 10 systems to Win 10 without buying a new license. If you did that, Microsoft recorded this fact in their central system. That period is over. What happens now if you take a pre Win 10 system, with a firmware OS key, and install Win 10? Does it work? My superstitious belief is that it does, even though it isn't MS's stated policy.