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Older iPods, such as the iPod Nano and iPods which have click wheels, store their music in a significantly easier to access format than do iPod Touches. If you want to transfer iPod Touch music onto your computer, use Sharepod. Click the iTunes app icon, which resembles a multicolored musical note on a white background, in your Mac's Dock.  If prompted to update iTunes, click Download iTunes and restart your computer when prompted. If you don't have iTunes on your computer, install it before proceeding. In order to prevent errors or accidental file overwriting, you'll need to change a few iTunes settings before proceeding:  Click iTunes in the upper-left corner of the screen. Click Preferences...  Click the Devices tab. Check the "Prevent iPods, iPhones, and iPads from syncing automatically" box. Click the Advanced tab. Check the "Keep iTunes Media folder organized" box. Check the "Copy files to iTunes Media folder when adding to library" box. Click OK You'll need to enable your iPod's Disk Mode feature in order for your computer to recognize it. The process for enabling Disk Mode varies depending on the iPod:   iPod Nano 6th or 7th Generation — Press the Sleep/Wake and either Home (7th generation) or Volume Down (6th generation) buttons at the same time until the Apple logo appears, then hold down the Volume Down and Volume Up buttons until the Disk Mode screen appears.  iPod with a Click Wheel —  Switch Hold on and off, press and hold Menu and Select until the Apple logo appears, release the buttons, and hold down Select and Play until the Disk Mode screen appears.  iPod with a Touch/Scroll Wheel — Switch Hold on and off, press and hold Play and Menu until the Apple logo appears, release the buttons, and press and hold Previous and Next until the Disk Mode screen appears.  iPod Classic — Disk Mode is neither supported nor needed when connecting a classic iPod to your computer. Click Spotlight {"smallUrl":"https:\/\/www.wikihow.com\/images\/e\/ea\/Macspotlight.png","bigUrl":"\/images\/thumb\/e\/ea\/Macspotlight.png\/30px-Macspotlight.png","smallWidth":460,"smallHeight":460,"bigWidth":"30","bigHeight":"30","licensing":"<div class=\"mw-parser-output\"><p>I edited this screenshot of a Mac icon.\n<\/p><p>License: <a rel=\"nofollow\" class=\"external text\" href=\"http:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a><br>\n<\/p><\/div>"} in the top-right corner of the screen, then do the following:  Type in terminal  Double-click {"smallUrl":"https:\/\/www.wikihow.com\/images\/1\/14\/Macterminal.png","bigUrl":"\/images\/thumb\/1\/14\/Macterminal.png\/30px-Macterminal.png","smallWidth":460,"smallHeight":460,"bigWidth":"30","bigHeight":"30","licensing":"<div class=\"mw-parser-output\"><p>I edited this screenshot of a Mac icon.\n<\/p><p>License: <a rel=\"nofollow\" class=\"external text\" href=\"http:\/\/en.wikipedia.org\/wiki\/Fair_use\">Fair Use<\/a><br>\n<\/p><\/div>"} Terminal  Type in defaults write com.apple.finder AppleShowAllFiles -boolean true ; killall Finder  Press ⏎ Return Plug one end of your iPod's charger cable into the iPod, then plug the other end into your computer. If your Mac uses USB-C ports instead of USB 3.0 (rectangular) ports, you will need a USB 3.0 to USB-C adapter to do this. Once your iPod's icon appears in the upper-left side of iTunes, you can proceed. Click the blue, face-shaped Finder app icon in the Dock. It's in the lower-left side of the Finder window. Doing so will open your iPod's window. If you can't find your iPod's name, click This PC on the left side of the File Explorer window, then double-click your iPod's name below the "Devices and drives" heading. Double-click this folder to do so. You'll find it inside the "iPod_Control" folder. Doing so will bring you to a list of folders with similar names (e.g., "F00", "F01", "F02", and so on). Click any folder here, then press ⌘ Command+A to select the entire folder's contents. Press ⌘ Command+C to do so. Go to a folder in which you want to save the music, then press ⌘ Command+V to paste in the music. Once you've moved the music onto your computer, you can add it to iTunes by doing the following:  Open iTunes if necessary. Click File  Click Add to Library...  Select your folder. If you don't see the music folders listed (e.g., "F00", "F01", "F02", and so on), you'll need to use the Terminal to make them visible to iTunes. In Terminal, change the directory to the folder where you pasted the music folders (e.g., cd the_name_of_the_folder_you_pasted_into). Then type xattr -c *. This will remove the attributes that are preventing iTunes from seeing the music folders. Click Open After successfully importing your music, you can type  defaults write com.apple.finder AppleShowAllFiles -boolean false ; killall Finder in Terminal to make hidden files be no longer visible again in Finder.
Understand that this won't work with iPod Touch models. Open iTunes. Change your iTunes settings. Put your iPod in Disk Mode. Enable hidden folder viewing. Attach your iPod to your computer. Wait for the iPod to display in iTunes. Open  Finder. Click your iPod's name. Open the "iPod_Control" folder. Open the "Music" folder. Select all folders inside the "Music" folder. Copy the folders. Paste the folders into a folder on your hard drive. Add the music to iTunes. Make hidden files not visible in Finder again if you want.