AC2 can be a real pain. Here is usually the stuff that causes this error:
~When you are going through setup make sure you disable the option to "Activate and complete enrollment".
~Also, delete your server under "Apple Configurator 2" > "Preferences" > "Servers" and re-add.
~Make sure you are grabbing the right Meraki link
~Is the WiFi WPA2 Enterprise (user/pass & cert.)? -- that seems to not cooperate sometimes.
~Purge AC2 program and files and re-start.
Jared
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