Crowd service not working

[Dave Mattinson]

I installed Crowd 4.2.2 using Java 11, which seemed to work fine.  I set it as a service with

service install crowd

that seemed to work and I added a few local users, which appeared OK.  After the following reboot the service failed to start and the only item in the event log failure is "Invalid argument" and nothing is updated in any of the logs (no indication of files being accessed, never mind being written to).

The initial log had a lot of Java messages, but as far as understand it that is normal.

Any clues what has gone wrong?

I can no longer start it manually.  I could initially.