Fixing volumes in Docker Toolbox

Charles Stover
2 min readSep 6, 2018

There is not a lot of documentation for Docker on Windows, and even less on harnessing the power of volumes therein. If you are like me, you may have spent a lot of time scratching your head over why your volumes simply aren’t mounting. There are countless help requests scattering the Docker GitHub and its relatives, and equally as many “fixes” that simply do not work.

So I’m here to report what worked both times that this has been an issue for me.

When running your container, use //x/ to reference your drive, where x is your lowercase drive letter. To reference C:\Users\admin\volume, you would use //c/Users/admin/volume.

Configure Oracle VirtualBox to have access to that folder. This is the important solution that is not well documented. Oracle VirtualBox, the virtual machine behind Docker Toolbox, does not have access to your folders by default. Mounting C:\MyFolder\ does nothing until you’ve given VirtualBox access to that folder.

  1. Find VirtualBox on your machine and run it.

2. Right-Click the default machine and choose Settings.