Can't connect to windows docker daemon

I updated my Windows machine to the latest version on the fast ring to get some access to awesome Windows container goodness. I followed the instructions at Microsoft’s MSDN but I got stuck trying to connect to the docker daemon to import the image.

C:\Users\Simon> docker load -i nanoserver.tar.gz
An error occurred trying to connect: Post http://localhost:2375/v1.21/images/load: dial tcp 127.0.0.1:2375: ConnectEx tcp: No connection could be made because the target machine actively refused it.

Turns out the solution is to put a file in c:\programdata\docker\config\daemon.json and inside that file put

{
    "hosts": ["tcp://0.0.0.0:2375"]
}

This will listen on any interface on port 2375. You might do better to put in

{
    "hosts": ["tcp://127.0.0.1:2375"]
}

which will at least limit connections to your local machine. Now everything else in the tutorial works as it should.