restored server.prefs from Time Machine which didn't help. Deleted
preference files, cache, database from the system preference panel and
now it's up and running.
But if server.prefs didn't fix the issue, then it didn't cause it in the
first place. No need to start from scratch if just one file is broken.
Search for other prefs or *.yml or *.yaml files in the cache and prefs
folder. It's rather large. It shouldn't be difficult to find.
Instead of wiping everything, you could have _restored_ everything from
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