Windows 10 Figure out when windows 10 was reverted to windows 7?

[lordcrekit]

Someone in my office has been downgrading windows on this machine and I need to figure out who.

 

[MikeHawthorne]

When I right click on my Windows folder and look at properties it shows when the folder was created, and that seems to correspond to when I updated to Windows 10.

Not sure it will show when it was reverted or not.