What happens if the external data source for my PivotTable is unavailable and I encounter the 'Data source reference is not valid' error?

If your PivotTable's source data resides in another workbook or is from an external source (like a database), ensure the source file is accessible and open, or the database connection is established. Check the connection string if the data source is from an external data source. Verify that the path and file name in the connection are correct, as well as database credentials if needed, and that the user has permissions to access the data.