Hi,
well, if the software connects (USB green), it is installed properly (including drivers). Check.
Now if it keeps asking for a key file, please make sure your VBar NEO is registered to your account and only then download the keys.sto file.
If you do multiple downloads, the file will be numbered, but the software can only detect the actual file name keys.sto.
So if in doubt, delete all key files in your downloads folder and inside the VBar NEO App and start over.
The key file is like a key chain, it can contain many units (always all the units registered to your account, at the time of the download).
Kind regards
Eddi
Born to fly ...
forced to work.