I am using Docker version 1.12.2, build bb80604 and VirtualBox 5.1.6.
I was able to install Docker Toolbox correctly but I am
You may need another couple of steps additional to what @programmerq mentioned.
C:\Users\\.docker\machine\machines\default\config.json VBoxHeadless.exe service from Windows task managerTry docker-machine rm -f default and docker-machine create -d virtualbox --virtualbox-memory 2048 default commands afterwards to remove/add default