I solved it (sort of). I reverted back to version 4.17.1. That also generated an error, but at least that error pointed to a solution. I went to ~\AppData\Roaming\Docker and looked at all the json files. For me, settings.json was binary and not valid json. I renamed that file and Docker started up fine. Not sure if that will fic 4.18, but I’ll try again when I have time.