I updated my zumo 390 today with Express for Windows 3.2.17.0 on my Windows 8.1 notebook and the download for the device failed. In advanced settings I had chosen for Device+Computer to install the new City Navigator EU NTU 2015.20 on, but the download of files for the device failed.
The download for computer was successful and I can use the City Navigator EU NTU 2015.20 in BaseCamp, before start int with the zumo 390 I did update my zumo 660 successful to City Navigator Europe NT 2015.20 to zumo660 and computer.
The files in the zumo390 should only be deleted after a successful download from the Garmin servers to a computer and not before. After this zumo 390 is useless, only the worldmap and the timezone map are there. Please correct this sequence in Express.
I did solve the problem by uninstalling Express completely including the choice to remove all user files, this clears up all previous download. I did also a run with Ccleaner program on program and registry, downloaded Express again, installed it and at this moment the download for the zumo 390 is completed and the computer is busy to send the files to the zumo over the usb kabel. ETF is now 5 minutes (Estimate Time to Finish (the job)).