Can't download a track from iCloud Music Library

See Identify cloud status icons in your music library on your Mac or PC - Apple Support. If you remove a local download of a track while its status is Waiting then you'll never be able to play that item because it hasn't been matched or uploaded. In addition Apple Music items can sometimes be withdrawn from the catalogue by the rights holders, which means they will no longer be available to you to play. It is always best to keep local copies and backups of your own media even when using Apple Music or iTunes Match.

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Some of your files might be too large, although those should show with an error rather than as blank. See Identify cloud status icons in your music library on your Mac or PC - Apple Support for details. Right-click a track that hasn't matched or uploaded and see if you can Add to Library. If not a possible approach to force tracks to be reevaluated is to create a new library that shows all of the content in the cloud. Locate a problem item, right-click, remove from library, then go back to the original library where the status should have changed to Removed. You should then be able to right-click and Add to Library to add it back in and hopefully have it matched, uploaded, or at least some status message generated.

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On the computer where the tracks play try File > Library > Update Cloud Library.

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