"Unable to program the requested memory region" message means that updater.exe successfully connected to the device and detected its HWID/UnitID/model and asked the device to erase some region, but it returned an error. So usb communication works fine. Also I think that corrupted NV memory can't cause this error, as the ramloader (boot.bin) doesn't use NV memory. That's why I think that your device's flash chip is faulty.