Q: Media/music folder duplicates

iTunes 9 [and later]: Understanding iTunes Media Organization - http://support.apple.com/kb/ht3847

Image of folder structure and explanation of different iTunes versions (turingtest2 post) - https://discussions.apple.com/docs/DOC-7392

In theory the new structure should incorporate all of the old ones.  To play it safe back up everything, then get rid of the old structure.  Personally I would stick them on a drive for a year or so.  Run with the newer for a while and see if anything is missing.

You can certainly try consolidating.  It will copy tracks located outside the designated media location in preferences to that location.  It doesn't add or delete media from the library, only relocates it.  If you then end up with similar looking numbers things should be okay.

Another way to have disparate sizes is conceivably you could have tracks in the first media folder that are not registered in your library.  It doesn't make sense in the normal course of iTunes operations but is possible.  Go with consolidating and see what happens.  If you're ever uncertain about doing a step, back up you computer then try.  If things don't go as planned you can restore from backup.

iTunes works this way.  You add a track. iTunes makes a note in its database file (the iTunes Library.itl file) which file on your computer to play when you click on a track.  Unless you have changed iTunes preferences settings so you manage your own media (in which case keeping track of it all is totally up to you then) everything iTunes has in its library should be in the main Media folder.  It used to be in a different structure but at some time in the past when you went from using iTunes 8 to iTunes 9 it should have transferred it for you after asking you.  It seems for a small number of people things did not go as planned so some end up with old structures alongside new.

If you have been managing your media you need to say so at the start because answers to any question where you are doing that will be very, very different, and 500% more complicated.  Are you managing your own media?

I use an older iTunes and it uses the old structure.  I cannot check if the "upgrade organization" button is still there in newest versions.  If it is, use it.  It will move any files iTunes has in its library to the new structure.  After that point any files left in the old structure are likely not known to your library and you will have to determine why that is.  Maybe you somehow got another copy in your library.  Maybe they were never added for some reason.  Without knowing the detailed history of your use of iTunes since iTunes 8 days we cannot say.    When it comes down to it, the only way to tell if iTunes is using a file in the new folder structure and play it 100% safe is to check the summary information in Get Info for each track for where the actual file is located iTunes will use.  No, I would not like to do this which is why I suggest speedier, more general methods, but archiving a copy of the files you delete just in case you see a broken link.

I have consolidate.  What I don't have is the "update iTunes to new organization" which is pictured in one of the links I provided at the very start.  As I already said, this should not add or remove anything from iTunes.  It should just make sure if there are any files in the old structure they are relocated to the new structure.  Even consolidate won't result in duplicates in iTunes.  It will result in unused files on your computer since it copies the files to the iTunes folder, it doesn't move them.  But nothing more is added to iTunes.

It is worth reading the help pages word by word as they are very specific in what they say (and sometimes do not).

The only way to guarantee you are missing nothing is to add everything to iTunes.  iTunes will ignore entries it already has in its database and will add ones it does not.  However, an entry is simply a file.  If you have two copies of that file, one in the correct new location and the other in the old folder, it will result in duplicates (likely many) because iTunes does not look at track information it looks at file location.  It will ignore the one in the new location it knows about already but it will add the other one which from your perspective will be a duplicate but for iTunes is a unique file entry.  This is why I suggest you update organize, put the supposedly no longer needed files on an archive drive, then use iTunes until you are sure nothing got missed.  It's either that or do a careful manual inventory of all your files and iTunes entries.

Limnos wrote:

 

...  I cannot check if the "upgrade organization" button is still there in newest versions.

The current wording is Rearrange files in the folder "<Media Folder>". The option is greyed out if the library is already using the newer layout. If so it still might be that files are in a mix of both new and old layouts. Turning Keep iTunes Media folder organized off and then back on again will enforce the active layout for all files. In either case this is done by moving files not copying them, but only applies to those files that are already inside the media folder and thus "consolidated".

tt2