Question about Microsoft Windows 10 Pro

No difference apart from a nicer box and a semblance of an instruction manual that is too brief to be of any use. Installation or reinstallation is the same. I have never had a problem with the OEM versions when upgrading the system, the MS phone server gives a serial number if the internet registration is refused! The 1 PC version is for 1 PC whether it is an OEM or Retail worm! BUT if you have a W7 pro or home worm uninstalled or not used you can in principle use its license number to activate an equivalent W10. Greetings

OEM license. The OEM (Original Equipment Manufacturer) licence for Windows is the cheapest but also the most restrictive licence. ... The big drawback of the OEM license (which explains its low price) is that it is tied to your machine for life, so it is impossible to move the license to another PC

The oem version is always installed on the same PC, (in case of problems) with an update but without help from microsoft, and the retail version is more expensive or (boxed) for several PCs with an update and help from microsoft if there are big hardware problems.