Apple Music windows app not letting me play older songs I have in my library

Do you have a current subscription to either Apple Music or iTunes Match? Are the items in question purchases from the iTunes Store or content ripped from CD or from other sources?

If you have tracks that won't play in your library, or won't transfer to a device, complaining that your computer needs to be authorized, and yet reauthorizing the computer doesn't fix anything, then you are perhaps looking at purchased tracks that haven't been decrypted properly after download. Assuming these are purchases, and you have backups, try right-clicking and removing the download, or deleting from the library without hiding from your purchase history, then redownload from the cloud links that should remain in the library. In some cases you may need to close and reopen before they show. While redownloading it may help to click the activity widget and turn off the option that allows for simultaneous downloads.

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