In their first Windows LTS release in two years, Canonical has released Ubuntu 20.04 for the Windows 10 Subsystem for Linux on the Microsoft Store.
The last release of Ubuntu was almost two years ago on May 2018 when Ubuntu 18.04 LTS was released and version 20.04 includes a wide range of improvements, program updates, and fixes.
For users who had previously installed the Ubuntu 18.0.4 LTS release, you may have issues upgrading it, but there is a workaround.
According to bkendig on Reddit, you can perform an upgrade to Ubuntu 20.04 using the following command:
sudo do-release-upgrade -d
If you run into an error stating “sleep: cannot read realtime clock: Invalid argument”, you should follow the steps in the Reddit post to move the /bin/sleep file temporarily, create an empty version, and then move it back after the upgrade.
The command shared by bkendig to temporarily move the sleep command is:
sudo mv /bin/sleep /bin/sleep~ ; touch /bin/sleep ; chmod +x /bin/sleep
Once the upgrade is done, move /bin/sleep~ to /bin/sleep and you should be good to go.
For users of Ubuntu 18.04 who rarely use it, it is far easier to remove the old versions and just install Ubuntu 20.04 from the Microsoft Store.