My 101 runs on x64 from win 7 upwards so its not that aspect.
Just so you dont go chasing a false lead.
X64 pro Win 7 is my goto box with FULL admin rights not just user admin rights.
Also have Driver enforcement turned off as I play quite a lot with so many Arduinos.
As another test you could enable the HIDDEN admin account log into it and also turn off driver enforcement to see if that fixes it.
Dont use the hidden admin account for anything other than testing BTW.
Yes facchinm is the man for this type of issue but I think he is more Linux ?