Error when trying to generate Autocomplete report: Unable to generate authentication token

Summary:

When I try to run the Personalization tool for the Autocomplete Rules, I get an "Unable to generate authentication token" error. What do I need to be doing differently?

Content (please ensure you mask any confidential information):

Full error message: "Unable to generate authentication token. Check Settings - Authorization and confirm all values are valid. Click Continue Anyway to generate a report of the existing Autocomplete rules. Click Exit to correct the Authorization Settings, verify Environment URL, Username and Password and re-run the tool."

Version (include the version you are using, if applicable):

25D

Code Snippet (add any code snippets that support your topic, if applicable):