Hiarchy of iTunes Folders, and Where Music ACTUALLY resides

The "missing file" issue with exclamation marks happens if the file is no longer where iTunes expects to find it. Possible causes are that you or some third party tool has moved, renamed or deleted the file, one of its parent folders, or the drive it lives on has had a change of drive letter, or you've moved a non-portable library to a different path (see Make a split library portable and/or Move your iTunes library to a new computer for details). It is also possible that iTunes has changed from expecting the files to be in the pre-iTunes 9 layout to post-iTunes 9 layout, or vice-versa, and so is looking in slightly the wrong place, or that you've been too aggressive when deleting duplicates. See Getting iTunes & Windows Media Player to play nicely if you're trying to access your media with any other media players.

Select a track with an exclamation mark, use Ctrl-I to Get Info, then click No when asked to try to locate the track. Look on the file tab for the location that iTunes thinks the file should be. Now take a look around your hard drive(s). Hopefully you can locate the track in question. If a section of your library has simply been moved, a folder renamed, or a drive letter has changed, it should be possible to reverse the actions. If the difference between the two paths is an additional Music folder in one path then this is a layout issue. I can explain further if that is the case. If everything is where it is supposed to be try Repair security permissions for iTunes for Windows.

In some cases iTunes may be able to repair itself if you go through the same steps with Get Info, or when playing a track, but this time click Locate and browse to the lost track. It may then offer to attempt to automatically fix other broken links. Although it says something like "use the same location" I think it expects to find the tracks in the same artist & album layout they were in previously, with one systematic change to the path.

If another application like Windows Media Player has moved/renamed the files, or the library has been moved from OS X to Windows, then the chances are that subtle differences in naming strategies will make it hard to restore the media to the precise path that iTunes is expecting. In such cases, as long as the missing files can be found somewhere, you should be able to use my FindTracks script to reconnect them to iTunes. See this post for an explanation of how it works. It might need some tweaking if your media is in a non-standard layout.

If you want me to try to provide specific advice please post back the following details:

1. The location of the media folder under Edit > Preferences > Advanced
2. The location of a sample missing track shown under Get Info > File > Location that begins file://localhost/
3. The true path to the file whose details you gave in 2

Note the addition of file://localhost/ (and the flipped direction of slashes in Windows) is normal for a file that isn't quite where iTunes is expecting to find it.

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See Make a split library portable for some general background. Exactly what happens to content that you add to iTunes will depend on the location of the media folder, the location of the files before you add them, your options for Keep... and Copy... under Edit > Preferences > Advanced, whether iTunes is using the new layout or the old one, and the embedded metadata in the file.

Purchases from the iTunes Store typically get downloaded to <Media Folder>\Music\<Album Artist>\<Album>\## <Name>.<Ext>

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iTunes may create duplicates if the same content is repeatedly added from outside the media folder when it is set to make copies of anything that is added to the library, or is added from an external drive that hosts the media folder that was offline when iTunes was launched.

Apple's official advice on duplicates is here: Find and remove duplicate items in your iTunes library. It is a manual process and the article fails to explain some of the potential pitfalls such as lost ratings and playlist membership, or that sometimes the same file can be represented by multiple entries in the library and that deleting one and recycling the file will break any others.

Start in the Songs view. Use View > Show Duplicate Items (pre iTunes 12.4) or File > Library > Show Duplicate Items (post 12.4) and then click Same Album to display exact duplicates as this is normally a more useful selection. You need to manually select all but one of each group to remove. Sorting the list by Date Added may make it easier to select the appropriate tracks, however this works best when performed immediately after the dupes have been created. If you have multiple entries in iTunes connected to the same file on the hard drive then don't send to the recycle bin.

Use my DeDuper script (Windows only) if you're not sure, don't want to do it by hand, or want to preserve ratings, play counts and playlist membership. See this thread for background on the script, this post for detailed instructions, and please take note of the warning to backup your library before deduping.

(If you don't see the menu bar press ALT to show it temporarily or CTRL+B to keep it displayed.)

The most recent version of the script can tidy dead links as long as there is at least one live duplicate to merge stats and playlist membership to, and should cope sensibly when the same file has been added via multiple paths.

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In iTunes click the menu item Edit > Preferences, and then select the Advanced tab. What is the location of the media folder listed there? It would normally be C:\Users\<User>\Music\iTunes\iTunes Media.

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Ah. Can you confirm that the active iTunes library file is E:\iTunes\iTunes Library.itl? If so with iTunes closed rename the inner iTunes folder as iTunes Media. Launch iTunes. Confirm the media folder under Edit > Preferences > Advanced now reads E:\iTunes\iTunes Media. If not use the choose folder button to correct it, then close iTunes and reopen. Check that your media still plays.

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