You are about to replace the data in the existing table. Preview the data you are pasting and verify that the structure (including ...

You are about to replace the data in the existing table. Preview the data you are pasting and verify that the structure (including column order and data type selection) matches the data you will be replacing. 

 If the first row of the copied data consists of table headings, you can specify that the row should be skipped when pasting into the destination table.