How do I make Ubuntu 20.04 work on Windows 10 WSL 2?

Question

I have followed the instructions of [Microsoft] (https://docs.microsoft.com/en-us/windows/wsl/install-win10) and [this] (https://www.omgubuntu.co.uk/how-to-install-wsl2-on-windows-10) verbatim. However, all I got is this error message which I cannot find further info. What did I miss?

Answer 1

In the end, I got everything working after:

1. using System Restore to recover the point immediately after the Win10 2004 update (that's actually the earliest restore point for my system)—be patient as it can take a while (also the first restart of the whole process)
2. enabling virtualization in BIOS (for my HP, it's under the tab Security->System Security->Virtual Technology->Enable)—the second restart
3. after Windows 10 restarted, navigating the Start Menu: Windows Settings->Apps->Optional features->More Windows features->Turn Windows features on or off to select both Virtual Machine Platform and Windows Subsystem for Linux (I didn't choose Windows Hypervisor Platform in the list)—the third restart ensued
4. after restarting, visit Microsoft Store from the Windows Start Menu and install Ubuntu
5. installing the Linux kernel update package (https://wslstorestorage.blob.core.windows.net/wslblob/wsl_update_x64.msi)
6. starting an elevated PowerShell session to run

wsl --set-default-version 2
wsl --set-version Ubuntu 2

7. Launching Ubuntu after the installation is complete. Create a new user account with password.

What I have now is Ubuntu 20.04 running nicely on Win 10 WSL2.