User-Mode Driver Framework: A device-driver development platform that facilitates the creation of drivers for certain classes of devices.

When a User-Mode Driver Framework (UMDF) driver that uses the Windows SideShow class extension processes a command asynchronously, the class extension may return a false error without fully processing the command. This problem may occur if the incoming input/output control (IOCTL) is not passed to the class extension component immediately or when the IOCTL is from a sequential queue.