Installing Kali 2016.1 on VirtualBox: Failure to Open Disk File

I'm trying to install kali_linux-2016.1-amd64.iso on VirtualBox 5.0.16 for 64 bit OSX and i'm having some trouble. I had kali install previously but i deleted it and i'm trying to reinstall kali and i keep getting this error you'll see in the picture below. I've went as far as uninstalling virtualbox and redownloading it. Also i redownloaded kali and even older versions of kali but i'm always confronted with this issue "Failed to open the disk file /Users/braindead/Documents/kali_linux-2016.1-amd64.iso"

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