Here is how to set up a VirtualBox Mac USB passthrough for your USB drive, card reader, iPhone, or other devices. So, if you ever wondered how to find a USB drive on VirtualBox in Mac, follow these steps below. USB Network Gate USB passthrough capabilities mean that all the convenience and efficiency of controlling USB devices that are physically connected to a remote computer with network/Internet access is right there in your hands, readily available through an elegant and straightforward GUI. Thanks to the redirection technology that works perfectly via LAN, internet, or Ethernet connection, any USB Network Gate user, be it any designer, software engineer, or game dev, obtains full control over the host machine’s printer, webcam, dongle, or other USB-based hardware. With this handy professional-grade app, USB redirection becomes an easy task because USB Network Gate solves many of the connectivity issues that users face when trying to access their USB devices from vBox VMs.
When you create your virtual guest OS, after VB is installed, you can then create the data for that system on any other drive if necessary.The easiest and most convenient way to establish VirtualBox USB Mac passthrough on a guest machine running a Mac OS (or other operating systems, for that matter) is using the software solution named USB Network Gate. It's only 250 MB, whch is smaller than iTunes.
It's an application that requires system extensions installed in our active Mac OSX system or current boot drive to function. You probably do not undertand the basic concepts of VirtualBox and neither Mac OSX that causes your misunderstanding in the first place. What you should have done is to install VB in your main or primary system and then create the virtual machine for Windows 7 on the external disk. It will fail when you do the next VB update. Rather than installing Mavericks on an external drive to install VB into it, you could have also simply moved the VB application to your external drive. It probably works because you have installed them already in your primary system from a previous installation. If you reboot your other drive, you are missing essential VB kernel extensions. That means you installed VB into another system. Asking Oracle to create a proper Mac app, what do you expect?
However, the VirtualBox auto-update will not find itself later if it is not inside the Application folder. VirtualBox is actually VirtualBox.app, which is a directory containing all the files and libraries it needs, except OS system extensions. Mac OSX, ever since Mac OS since 1984 does not use or need a concept of software uninstallers likes Windows and typically does not require to specifiy install locations. If you want, you can move the VirtualBox application out of the Applications folder anywhere else, after the instalaltion, like you can do with pretty much all proper Mac applications.
It will have to install some system kernel OS extensions and application support files, which can only be installed in your OS system or boot drive and only for all users. VirtualBox is an application that provies a type 2 hypervisor with hardware assisted virtualization. What you are doing here is only to install the software necessacry. You are apparently confusing the installation of VirtualBox with configuring or setting up a virtual machine.