When I run DBMigrator on Windows, it gives me this error: "Drive Name: A:\: error querying space: java.nio.file.FileSystemException: A:\: The device is not ready."
That error message is caused by a bug in the DBMigrator tool. It's a harmless message and doesn't actually indicate a problem. It will still migrate your catalog.
We have reported this issue to our developers and have requested a bug fix.