Diagnosis
You chose Edit -> Table control, but a screen element of adifferent type already exists at the current cursor position.

System Response
Function not executed.

Procedure
If you want to create a table control, place the cursor on a free spaceon the screen and choose either Edit -> Table control orEdit -> Create element -> Table control.
If you want to edit or display a table control, place the cursor on thetable control and choose Edit -> Table control.