Use the ForeColor property to change the control's foreground color. Use the BackColor property to change the control's background color. Use the ForeColorRich property to change the color used to paint the mask, while the control's Type is RichEdit, and the Value is not yet validated. Use the Valid property to check whenever the control's mask value is valid or invalid. The BackColorReadOnly property specifies the control's background color when the field is locked ( ReadOnly property is True ). The ForeColorReadOnly property specifies the control's foreground color when the field is locked ( ReadOnly property is True ).