When you start a new worksheet and use Data > Get External Data > New Database Query, select a data source and click on Show Tables, Microsoft Query X displays the tables dialog, but no tables are shown. You can click on lines in the tables dialog and scroll up and down, but all the table names are blank.
The reason for this is that the Microsoft SQL Server ODBC driver describes the table name column as SQL_WVARCHAR, but Microsoft Query X does not handle SQL_WVARCHAR column types. To work around this, you need to add:
DisguiseWide=1
to the data source you are using.