By default, the MarkTooltipCells property is False. If the MarkTooltipCells property is True, the control paints on the right side of the cell a sign that indicates that the cell has associated a tool tip. Use the CellTooltip property to associate a tool tip to a cell. Use the TooltipCellsColor property to change the color used to sign cells that have tool tips. Use the MarkTooltipCellsImage property to assign a different look for signs to mark the cells that have tooltips.