Export Wizard Column Mappings: Destination (Excel) Columns Not Showing

I've researched this for hours but I'm still getting this error (see below). My setup:
SQL Server 2014 Express.
Exporting a table called 'locations' to Excel 2010, file name = "SqlExport.xlsx".
The worksheet is empty except for column headings which are identical to those in the 'locations' table.
I've saved the workbook and closed it.

In the wizard:
Choose a Data Source:
    SQL server Native Client 11.0
    Server Name: 'machine\sqlinstance'
    Windows Authentication
    Database: 'Staging'

Choose a Destination:
    Microsoft Excel
    Excel file path: C:\Users\Tim\Downloads\SqlExport.xlsx
    Excel version: Microsoft Excel 2007
    'First row has column names': checked.

Specify Table Copy or Query:
    'Copy data from one or more tables or views': selected.

Select Source Tables and Views:
    [dbo].[locations] is the only source table checked
    destination is 'Data$' which is the correct sheet name.

Column Mappings:
    'Append rows to the destination table': checked
    The source table column names are listed but the destination columns all say '<ignore>'

So the problem is that SQL Server can't see the Excel columns to export the data to. Any ideas anyone? Thanks.

Tim

- Validating (Error)
 Messages

Error 0xc020201b: Data Flow Task 1: The number of input columns for Destination - Data$.Inputs[Destination Input] cannot be zero.
 (SQL Server Import and Export Wizard)

Error 0xc004706b: Data Flow Task 1: "Destination - Data$" failed validation and returned validation status "VS_ISBROKEN".
 (SQL Server Import and Export Wizard)

Error 0xc004700c: Data Flow Task 1: One or more component failed validation.
 (SQL Server Import and Export Wizard)

Error 0xc0024107: Data Flow Task 1: There were errors during task validation.
 (SQL Server Import and Export Wizard)

timSF