Please use the network update method.
Make sure, the device in idle state (no playback or recording)
Connect the uTrack24 network cable to the network where your PC/MAC connected (you can connect directly to your PC/MAC as well).
Check the IP address on the uTrack24 (settings/utilities/system details)
Type this ip address to your browser (Chrome or safari preferred)
Drag and drop the bcd file from your file browser to the browser update screen.
You should see a progress bar on the uTrack24. When is done, select the reboot in your browser, or manually power cycle the uTrack24.
If you see any error message in your browser please let me know.