I just hit this same issue. It does NOT look the same as the driver signing issue, so I had not been disabling driver enforcement. but I looked in the event logs and did trace it to the same issue. Disabling driver enforcement solved it. And when I was googling I saw a Stack Overflow thread saying the arduino driver signature expired Dec 19th?
So hopefully that will get fixed up soon, or whatever this is gets fixed up. And the expiration would explain why this worked for me last month but not this month!