Many installable drivers support a private configuration dialog box that lets the user configure the driver and associated hardware. To determine whether a driver supports such a dialog box, an application calls the SendDriverMessage function and issues the DRV_QUERYCONFIGURE message. If the driver is configurable, this function returns a nonzero value. If it is not configurable, this function returns zero. If the SendDriverMessage function returns a nonzero value, the application displays the configuration dialog box by calling the SendDriverMessage function a second time and sending the DRV_CONFIGURE message.
If the driver supports a private configuration dialog box, it should display the dialog box and process user input when it receives the DRV_CONFIGURE message. Typically, any configuration data specified by the user is maintained in the [drivers] section of the Windows SYSTEM.INI file.