iTunes has updated but I have lost a lot of my music
My laptop has my iTunes music but after update it has only downloaded a fraction of this
Windows, Windows 10
See Empty/corrupt iTunes library after upgrade/crash - Apple Community.
If you installed Apple Music, Apple TV, or Apple Devices it is normal to find that iTunes now only shows Audiobooks and Podcasts. Remove any of those three that have been installed and you should be able to choose Music from the media selector once more.
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