Explanation: When a new build of Foxhound is installed, the data upgrade portion of the post-setup process fails with the message "Authentication failed".

Foxhound is not licensed to run using an "OEM" or "Authenticated" edition of SQL Anywhere.

Try installing a regular non-OEM edition of SQL Anywhere. Then rerun the upgrade, including the initial "unsetup" step: How do I install a new version of Foxhound?

Note: A fix for this problem will be delivered in the next Generally Available build of Foxhound.

See also...
How do I install a new version of Foxhound?