homebrew-cask

I'm trying to install virtual box with brew-cask, but That returns this kind of error and I cannot install virtualbox. I use MacOSX Lion 10.7.5 and homebrew 0.9.5, ruby 2.1.0-p0 I've described the process in Terminal below. First of all, brew tap command is succeeded. $ brew tap phinze/cask Cloning into '/usr/local/Library/Taps/phinze/homebrew-cask'... remote: Reusing existing pack: 32538, done. remote: Counting objects: 36, done. remote: Compressing objects: 100% (36/36), done. remote: Total 32574 (delta 16), reused 2 (delta 0) Receiving objects: 100% (32574/32574), 11.72 MiB | 379 KiB/s,

After installing and uninstalling some programs through brew and brew cask , now I get brew doctor saying "unlinked kegs in your Cellar". It suggests to link them, to avoid build trouble with later brews, but instead I'd rather delete them, as they're leftovers from brew programs or formulas that I don't use anymore. How or where do I remove these? (I don't even know what a keg, or the Cellar, is) Run: brew remove packageName for each unlinked package. running brew link will bring up optional commands that you can use, along with that you'll need an argument to go with it or it'll prompt you