After a couple days of erasing duplicates tracks in Itunes on my maxed-out MacBook Pro (Retina, 13-inch, Late 2013), I started getting a weird anomaly. The tracks were gone but the space that should have been freed up wasn’t there. I was alerted to this when my OS kept warning me I was running out of space. But how could this be if I was erasing files? I tried the obvious and restarted the computer hoping it would eventually correct itself, but it essentially started crippling my computer as it became sluggish for lack of space. Rather than keep erasing mp3s I decided to back my library (and anything else of importance) and take my laptop to Carbon Computing on Queen St. in Toronto to get them to do a fresh install. Since, I was in the market for a new DJ controller, I figured why not upgrade to an OS that could fulfill my Serato Scratch Live and Serato Dj needs (which was Yosemite). The result of installing a new OS on my computer, it shed a 100 gigs of space on my hard drive. I am realizing this is sounding like a weight loss commercial but really though! The task I set out to do, which was more or less to free up my space to add a new OS, more or less happened backwards. So, I didn’t get to go through my entire library, but ultimately fate decided for me: its better to go through an edit your library as it happens than sit down and try to do the whole thing at once. Its a daunting almost impossible task to achieve if you have an extensive mp3 library. What is more, better quality version of songs come along all the time, so you are better off just erasing duplicates as you see them.