Note that absolutely none of this is authoritative or directly based on relevant documentation. It’s mostly what I found and figured out and guessed and (in some cases) made up. Some of it may be wrong or dangerous or lead to disaster or confusion. I am not taking responsibility here for anything. Read and act on it at your own peril!

If this happens to your Ubuntu installation in WSL:

Failed to take /etc/passwd lock: Invalid argument
dpkg: error processing package systemd (--configure):
 installed systemd package post-installation script subprocess returned error exit status 1
dpkg: dependency problems prevent configuration of systemd-timesyncd:
 systemd-timesyncd depends on systemd; however:
  Package systemd is not configured yet.

dpkg: error processing package systemd-timesyncd (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of udev:
 udev depends on systemd | systemd-standalone-sysusers | systemd-sysusers; however:
  Package systemd is not configured yet.
  Package systemd-standalone-sysusers is not installed.
  Package systemd-sysusers is not installed.
  Package systemd which provides systemd-sysusers is not configured yet.

The solution (or workaround) might be these commands:

sudo sed -i -e '/systemd-sysusers/s/\.conf$/.conf || true/' /var/lib/dpkg/info/*.postinst
sudo dpkg --configure -a

at least this is what Chatgippity told me.

If it turns out that it doesn’t work, I’ll correct or update this post as necessary.

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