Setup
Windows 10 Pro (1511 + all updates)
Connected to a Domain Controller
Use Case
I'm working remote, usually on (slow/high latency) mobile networks (3G,4G).
The connection to my corporation is done via a Cisco VPN Connection. On
Windows, I use shrew to establish that connection (www.shrew.net).
Symptoms
After I establish the VPN connection it usually takes a couple of minutes,
but then, one of my CPU Cores is maxing out. Using the Resource Monitor,
I can see, that the gpsvc (Group Policy Service) is using up all CPU time.
However, that happens in maybe 80-90% of the time. In rare occasions,
there is no problem at all.
Disabling the VPN Connection does not help. Once the CPU is maxed out,
it never goes back down. I have to restart Windows to get sane CPU usage
numbers.
This problem exists at least since Windows 8.1. I did countless from the scratch
setups with various windows versions. They all show the exact same behavior.
If I remember correctly, the event log show different entries for the high cpu
usage case. If a Microsoft Technician reads this, I might be able to get the log
entries of both states.