Bash on Ubuntu on Windows (10) - Unable to connect to Upstart

This has been discussed before. It's a known issue and the quick-fix suggested by Canonical is to run :

cat > /usr/sbin/policy-rc.d <<EOF
#!/bin/sh
exit 101
EOF
chmod +x /usr/sbin/policy-rc.d
dpkg-divert --local --rename --add /sbin/initctl
ln -s /bin/true /sbin/initctl

A real fix is available but not yet released to the Fast Ring:

A fix for the udev apt update issues is on it's way to the flighting branch. When the fix reaches the branch new subsystem installs will no longer have this issue.