Warning : MBR.Bin could not be created

I have followed the the guide for How to Create and Deploy Images via Console Without Installing the Remote Client found here

https://www-secure.symantec.com/connect/articles/how-create-and-deploy-images-console-without-installing-remote-client

but I keep getting the error message "Warning : MBR.Bin could not be created"

I have a usb stick that loads up my PE environment and gives me a Network address ok and starts up NGCTW32.EXE -Console ok.

The console cmd window starts up and polls correctly to my console server, and I can see it in the default group folder.

However if I run a task - it shuts down and loads back into the operating system of the host machine (which in this case does not have the client installed)

The task I am running is to just copy a file to the C: drive of the machine.

The console event details pane shows "Details for : To Target operating system - Failed to reboot client to new OS"

Any help appreciated

thanks