When my windows 10 automatically updated to the anniversary edition (build 1607) I could not get Docker for Windows to start anymore. It was showing in my task manager as running but nothing was shown in the system tray and I could not connect to it. To fix this you can take the following steps.

• Reactivate Hyper-V: For some reason after the update Hyper-V was dissabled again
• Optionally remove Docker for Windows: I was running still the beta version so just to be sure I uninstalled this version
• Disable your network
• Reinstall Docker for Windows
• Reboot
• Now you should see Docker for Windows starting in the tray. Wait for it to fully be started
• Enable your network again

  Why this is happening is being investigated in the following repo: https://github.com/docker/for-win/issues/27