In recent Dell notebooks (but I guess that this is valid for other vendors too) that are already sold and delivered with the preinstalled operating system is no longer located on the bottom of the laptop's famous sticker with the microsoft operating system serial.
This is because the serial is integrated in the laptop bios, and the operating system is already automatically activated. However even entering the bios there is no way to view the serial. This thing is also listed on the official page of the Dell:
http://www.dell.com/support/article/us/en/19/590806/%7Bdoclang%7D
Besides, with the latest versions of the o.s. all those serials detection software that show you all the codes inserted / used by installed sw do not work anymore (at least as regards the o.s. serial).
So how can you get the serial?!?!!? After a few months in which I wasn't able to find a solution I have finally found it!
You should download this sw that lets you read the informations saved in the bios:
http://rweverything.com/download/
run it, go to the tab ACPI Tables -> MSDM tab and there you will find your serial finally!!!! WOWOWWOWOWO simple….. if you know how to do it… and what sw to use…. indeed the sticker attached to the bottom of the PC was a bit archaic in a digital world…. but it was definitely more convenient and affordable for everyone! 😐