Use the Columns page of the Excel Source Editor dialog box to map an output column to each external (source) column.
To learn more about the Excel source, see Excel Source.
Available External Columns
View the list of available external columns in the data source. You cannot use this table to add or delete columns.
View external (source) columns in the order in which the task will read them. You can change this order by first clearing the selected columns in the table discussed above, and then selecting external columns from the list in a different order.
Provide a unique name for each output column. The default is the name of the selected external (source) column; however, you can choose any unique, descriptive name. The name provided will be displayed within SSIS Designer.
Integration Services Error and Message Reference
Excel Source Editor (Connection Manager Page)
Excel Source Editor (Error Output Page)
Excel Connection Manager
Loop through Excel Files and Tables by Using a Foreach Loop Container