Move iTunes library from one folder to an external hard drive on a PC

Step 1. Connect the external storage device to your PC or Mac.

Connect the external drive to your PC and give it time to load up before it shows up on your computer.

Step 2. Find iTunes Library Folder

To locate the iTunes folder on your Mac, choose Go > Home > Music > iTunes in the Finder menu.

To locate the iTunes folder on Windows, go here:

• Windows XP: \Documents and Settings\username\My Documents\My Music\

• Windows Vista: \Users\username\My Music\

• Windows 10/8/7: \Users\username\Music\

Step 3. Go to iTunes Advanced Settings

Open iTunes > Preferences (Mac) or Edit > Preferences (Windows). Then, select the "Advanced" tab in the iTunes Preferences window. Next, check the "Keep iTunes Media folder organized" and "Copy files to iTunes Media folder when adding to library" boxes. Then, click "OK" and close the Preferences window.

Step 4. Consolidate your iTunes Library

You're recommended to consolidate your library before moving the iTunes folder to external storage because consolidation ensures everything in your library is stored in one place.

To consolidate your media:

1.Open iTunes and choose File > Library > Organize Library in the menus

2.Select "Consolidate files."

Step 5. Move/Backup iTunes Library to External Hard Drive

1.Quit iTunes and open the iTunes Folder on your computer.

2.Drag the iTunes folder from your computer (Mac or Windows) and drop it on the external drive. All files in iTunes Folder will be copied to the external drive. The process could take a while depending on how large your collection is.

3.Now that your collection is safely stored in the external hard drive (or another location that you chose), you can delete (some of) the files at the old location to free up some space in your hard drive.

Note:

An important thing to note here is that you’ll need to connect the external media every time you open iTunes for if not, the media files aren't going to show up. If you open iTunes without your external hard drive connected, iTunes will give you an error message saying the "Library cannot be found." Quit iTunes, connect the external hard drive and reopen iTunes to fix.

Thanks

See Make a split library portable - Apple Community for more on this. Typically if your library is in the standard shape (iTunes folder containing library files and an iTunes Media folder containing all media) you can copy the whole iTunes folder to your external drive, then shift-start-iTunes to reconnect to it on the new path, and it will all work.

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