In fact, we can download Spotify app from Spotify's official website or from the Windows Store. If you are using the Spotify for Windows app, then you might likely get the unknown error. So we highly recommend that all users download the Spotify app through Spotify official website rather than the Windows Store.
If you are using the Spotify app downloaded from Spotify's official website but still getting this error, please contact us by submitting a request with the detailed information including the version number of your TuneFab Spotify Music Converter, the version number of your Spotify app, the operating system of your computer and the error screenshot.
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