mkrzero not recognized by windows 8.1 64-bit

hello.
I've just bought 5 MKRZERO dev kits.
I have installed the Arduino 1.8.0 IDE on 2 PC's, one running windows 10 and the other running Windows 8.1 64.
The windows 10 properly detects the MKRZERO and can program it.
The windows 8.1 can not do that - the main reason is that it fails to properly install its driver.
How can I solve that?

Thank you

Win 8 does have driver enforcement issues.

There are a plethora of results in google and not just for Arduino.

Here are a few results and at least one of them should work for you

thanks. problem solved

  1. disabled the windows driver signature.
  2. uninstalled and re-installed the drivers, via Arduino IDE->Tools->Boards->"Arduino SAMD Boards (32-bits...)".
  3. got the windows red alert window, asking if I want to install from an untrusted source.
  4. I clicked "Yes".
  5. Plugged the MKRZERO - it got recognized with a virtual COM port.