When you are updating existing data in the system, it is best to first download the existing data. This ensures that you have the most recent data from within the system, which helps ensure accuracy.
To download the existing data, open the Data Load Wizard, select the type of data you are loading, and on the Upload page click the link in the lower-left corner. This takes you to the appropriate report page for the selected data type, if available. If a report is not available for the type of data you are loading, you are taken to the Custom Reports page where you can create a custom report to extract the appropriate data. See Custom Reports Overview.
When getting existing data, please consult the system requirements outlined in the Helpful Hints to ensure that the data is ready for loading.