Could you please try upgrading to the .NET MF 4.2 QFE2 SDK and the Netduino 4.2.0.1 SDK on the downloads page?
You'll need the new WinUSB drivers for the device to work once TinyBooter is flashed.
I tried to install both packages, but they told me that they are already installed (that could be right, I reinstalled my system not long ago) - but now I looked in my installed programs and there are these versions listed:
- Microsoft .Net Micro Framework SDK 4.2 (QFE1)
- Netduino SDK v4.2.0 (August 2012)
After manually uninstalling them and installing the newest version these versions are listed:
- Microsoft .Net Micro Framework SDK 4.2 (QFE2)
- Netduino SDK v4.2.0 (August 2012)
Now I redeployed the bootloader and the firmware and it seams to work.
Thanks!
Stefan