target kernel debugger


My target PC is a Win10x64Prof, debugging is enabled and I could debug my kernel drivers since 2019 until today.
After a WIN10 update on the target PC today it stopped working.

What happens:

  1. Host: Run Windbg
  2. Target: boot up
  3. Host: “Connected to target on port 50000 on local IP”
  4. Host: several lines as usual like “Path validation… etc”
  5. Host: KDTARGET Refreshing KD connection.
  6. After this line the communication between target and host stops. Host does not get anymore UPD packets from the target. It is obvious that the target sends some packets while booting, but after the OS has loaded communication stopped.

I run:

  • bcdedit => debuggin is on, busparam ok
  • bcdedit /dbgsettings are correct
  • kdnet shows:
    "Network debugging is supported on the following NICs:
    busparams=5.0.1, name of my network adapter

KDNET initialization failed. Status = 0xC0000001.
No valid link. The network cable might not be properly connected. "

The cable is properbly connect, ping and all network communication is working, and moreover the traget and host could communicate while the target was booting.
Wireshark on the target shows that no more packets were send to the Host.

What could be the reason that “KDNET initialization failed with the error msg above”?

Any help is appreciated,
Thanks Dietmar