Content originally posted in LPCWare by Tsuneo on Tue Nov 27 14:40:14 MST 2012
Did you update the driver of the target device to generated one?
On Device Manager, identify "USB_Device_with_DFU_Capabilities" device (maybe, LPCXpresso demo?). Right click on the device instance, and "update driver". In the dialog, specify the path to generated folder as the driver location.
Tsuneo