Explanation:
This message occurs during a TABLELOAD run when source and target table look the same but differ internally, because the source table contains "invisible", dropped, columns which have not been created in the target table.
User Action:
If you decide by keystroke to continue the execution, the history of the source table concerning the dropped columns is taken over for the target table. But you may also abort the loading of the table. In this case, the TABLELOAD run is continued with the next table.