Hello everybody. I wrote a wdf filter driver for the usb device. When EvtIoWrite triggers, I want to change the data and put it on the device. I tried to use these methods WdfRequestRetrieveInputMemory, WdfMemoryCopyFromBuffer and WdfMemoryCopyToBuffer. But after sending this request to the next driver, there is a fatal error 0x00000023: FAT_FILE_SYSTEM. If you can explain the principle or give an example, I will be very happy. Thank you.