iTunes backup problem
I wanted to backup all my iTunes songs so what I did was copy the iTunes folder with all my songs onto an external HDD. I have 1594 songs in my iTunes. Just to test my backup, I install iTunes on my brother's laptop and selected "Add Folder to Library..." in iTunes. However, only 1584 songs were added. I don't know which 10 songs are missing (would take too long to check). I know all my songs were backed up onto the HDD because the size of the backup is the same size as the iTunes folder I copied to the HDD.
What's wrong? What should I do?
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Microsoft Windows 8 Pro 64-bit