iTunes says 131.33 GB, Finder says 177.88 GB; how to reconcile?

[mikebw]

This began when I decided to upgrade from a 250GB Music drive to a 400GB Music drive (not solely for iTunes). I copied the entire iTunes Music folder to an external drive, swapped out the 250 for the 400, then copied the folder back from the external to the 400. When it was done I got an error saying some of the items were skipped because of permissions issues. I then set permissions to read/write for all enclosed items remaining on the external drive and used rsync to copy all the missing files to the 400 drive and set the location of the music folder within iTunes to the new location on the 400 drive. Seems like all my files are there, that is to say anything in my iTunes library can be played without any problems, however there is now a discrepancy in the size of the actual folder containing the music files in the Finder as compared to the size of the library reported within iTunes.

I am not sure how to get iTunes to re-scan the Music folder on this 400 GB drive to add any missing files without losing all my playlists and rating info.

I suppose it is possible there are some duplicates in the actual Music folder that are not being displayed in iTunes that could account for the 46GB difference. Any ideas?

[mikebw]

Update- Looks like rsync didn't quite work at I intended and there are now duplicate files in the iTunes Music folder on the 400GB drive. I guess I can just re-add the whole folder to iTunes and then show duplicates and then remove and delete the dups. That should leave just one copy of all the files in both the Finder and within iTunes.

[deckeda]

There will be a small discrepancy between how 10.6 and later summarizes file sizes and iTunes, which as far as I know does it's own calculation based on the old way. http://support.apple.com/kb/TS2419 But not as large as you have.

Finder shows 555GB for my Music folder, iTunes says I have 526GB of music. I would expect your difference to be less. Then again, with over 14,000 items I doubt my Music folder is 100% accurate.

If everything's there, then everything's there and you don't need to rescan.

But if you DID want to rescan it's easy and non-destructive. Just drop the Music folder, or even the entire iTunes Media folder in iTunes' "LIBRARY" section (upper left portion of iTunes window) and everything will get reindexed and added as necessary. It won't create duplicates unless your location info had been changed.

Either way, playlists and ratings aren't affected, because that info isn't stored with your song files. That's in the two library and xml files instead.

[mikebw]

Thanks. I am beginning to think the error about not being able to complete the transfer of files was a red herring. I am having iTunes to the re-scan now and will just remove any dups as needed.

[mikebw]

Just finished re-adding and then removing all the duplicate files from the drive. I am down to about a 10% discrepancy now which seems about right.