I had installed WSL (Windows Subsystem for Linux) a long time ago to gain access to Ubuntu 14.04 LTS directly from my Windows 10 Desktop. However, as time passes, Software grows old. Upgrading the Ubuntu Subsystem via apt-get update / do-release-upgrade should work, but that could have some nasty sideeffects, considering that the 14.04 LTS WSL release had been a beta test - so, a reinstall should be better.
Luckily, TechRepublic got this covered. Just open a CMD and run:
lxrun /uninstall /full /y
to uninstall the current WSL version.
Afterwards, try
lxrun /install
to reinstall it. With this "reinstall", Ubuntu 16.04 LTS will be installed.
Nonetheless, I recommend a nice
sudo apt-get update sudo apt-get dist-upgrade
afterwards in your BASH session to get the WSL to the latest version ;).