One of the most severe symptoms is when Windows detects a "USB Mass Storage Device" but shows "No Media" with a capacity of 0 bytes. This typically indicates that the controller's firmware is corrupt and cannot load from the NAND. In this scenario, the MPTool may not auto-detect the drive. To fix it, you may need to force the controller into "ROM mode" (often shown by a VID of FFFF ), which requires physical manipulation of the flash drive's circuit board by shorting specific contacts on the controller.