I know whats wrong, and I also know it's bloody hard to fix it.
Basically in the last few years, there has been a wave of HP and DELL PC's that use common chipset BRANDS, with a very obscure MODEL.
They're literally similar enough that Windows will (automatically) install the driver, but then nothing will work as it should.
Common symptoms are USB not working, and more commonly, Ethernet showing as "Connected" but no data can go through (well, packets send, and receive, but they must be 'wrong' somehow, because no network access).
ASROCK is currently doing the same on AM4 and it's ticking me off.....
Windows 7 CD keys can activate Windows 10 now, so I'd STRONGLY advise a clean install. There's always the chance that Windows10 will "reference" the installed drivers when upgrading and you'll end up in no better position.
While this is unfortunate, because you're copping the blame, feel free to quote me when I say THIS and exactly THIS is why you DON'T buy pre-packaged PC's.
They're hard to support, and hard to troubleshoot.
All this is why, to this day, a PCI and PCI-E network card is a staple in my "IT fix it" bag.
Good Ol "Intel 10/100", always giving.Go to the full post