There are many alternatives to iTunes for Windows and since it's discontinued a lot of people are looking for a replacement. The best Windows alternative is MusicBee. It's not free, so if you're looking for a free alternative, you could try MusicBee or Clementine. If that doesn't suit you, our users have ranked more than 100 alternatives to iTunes and loads of them are available for Windows so hopefully you can find a suitable replacement. Other interesting Windows alternatives to iTunes are foobar2000, AIMP, Winamp and Audacious.
The best non-open source app for Windows that plays music. Great at organizing music collections and even suggests local gigs based on bands you have stored in your library. But I would go for an open source alternative, and MusicBee doesn't help me have the same library on non-Windows machines.