When is 10 not really 10

I had to work on a customer/friends PC today, where after an MS update, the Classic Shell would no longer work.
His beautiful desktop with all his program icons on it was just GONE.
I won't go through all the details of how I tried to fix that, but finally when I looked at the possibility of doing a Factory Restore, I was horrified when Windows told me that it would restore the OS back to Windows 7. WTF???

This was on a Lenovo Desktop about a year old, bought with Windows 10 Home/64 installed.

All I could figure was that Lenovo had some old Windows 7 PC sitting around in the warehouse that they wanted to sell and they did an UP-grade on them to Windows 10 Home, so they could sell them as NEW PC's.
How else could this debacle happen?

Well, I finally got the PC to where my customer/friend could use it, sort of, but it's sure not back the way he wants it.
From everything I saw today, only a wipe and reinstall of Windows 10 will completely fix the problem.
One more problem that I found....when a window is in full screen mode, I could not reduce it with the little icon it the upper Right Corner of the window. Clicking that icon did absolutely Nothing!

If you were that Lenovo customer, what would you do?

Maybe I could take a poll......

TechnoMage

With a PC that's over a year old, now, it's a little late to file a complaint. Eh?

I know he bought the PC over the internet, but I don't know from whom.
I set the PC up for him, when he first got it, but I had no indication that it was a Windows 7 PC, upgraded to Windows 10.
I think he's learned a lesson about buying a new PC, and so have I.

Personally, I build my own PC's and install the OS myself, so I know exactly what's in the 'Box'.

Thanks for you input,
TechnoMage

A clean install would be the way to go, since the Recovery Partition is Windows 7, there will be no reason to keep this partition. Wiping the whole drive and reinstalling, no matter how painful, would be the way to go.
If you want to try and repair what you got, press the Win Key+X and choose Command Prompt (Admin). Type
SFC /scannow and press enter. This will replace any missing system files.
If that doesn't help, try Enabling the Hidden Administrator account, log out as the user and login as the Administrator. See if the computer is more responsive, if so, then Create a new User Account and copy the user files to it and use that account.
Also, uninstalling Classic Shell, Restarting and Reinstalling it, should bring it back.