All former users of iTunesBy the time Apple released iTunes 11 in November last year, they realized there were some features that had changed or simply disappeared. One of the changes was located on the work screen since now it did not have a left sidebar in which to manage the contents of the library, which was quickly solved by looking at the "View" menu and clicking on "Show sidebar".
Now, when users went to delete duplicate songs from the library, they found that Apple had removed this feature. It was a function that iTunes had truly lost in the new version, that is, it was not located anywhere else in the application. It had literally been eliminated.
We all used this feature to clean our library and thus save a few megabytes of space. Luckily, Apple brings the feature back to iTunes 11, at version 11.0.1. We can find it in the "View" menu and then in "Show duplicate items".
After doing this, we will see that the songs and their duplicates will appear immediately in the central area of the window. We must be careful not to select all those files and delete them, since iTunes shows you as many files of the same as you have copies of the same, that is, it does not save any in another place, so if you delete the three same files that it shows you, you will have completely deleted that song.
After reading the above, you will ask yourself: Are all the songs that he teaches me exactly the same? To be totally sure, you should look at the properties of each song in case of doubt in case one has a different recording quality than another.
More information - iTunes turns 10. Congratulations!
Source - Cult of Mac