Smart settings allow your virtual machine to also use the U disk

The first step: run the VirtualBox first, but do not run the virtual system, the real machine insert U disk, the virtual machine settings according to the following figure:

　　Step Two: if you encounter a hint, the lack of "Oracle VM VirtualBox Extension Pack", you need to download first: https://www.virtualbox.org/wiki/Downloads, no prompts error, You can skip this step.

VirtualBox 4.1.4 Oracle VM VirtualBox Extension Pack all platforms

Support for USB 2.0 devices, VirtualBox RDP and PXE boot for Intel cards. The chapter from the User Manual for a introduction to this Extension Pack. The Extension Pack binaries are released under the VirtualBox Personal use and evaluation License (Puel).

Please install the extension pack with the same version as your installed version of virtualbox! If you are are using VirtualBox 4.0.14, please download the extension pack here.

If you are installing a VirtualBox 4.1.4, click "All Platforms" and download the installation and can.

　　Step Three: if you bump into "You can move this by adding your user to the ' vboxusers ' group." This error tip:

Failed to access the USB subsystem. VirtualBox is isn't currently allowed to access USB devices. You can change this by adding your user to the ' vboxusers ' group. Please, the user manual for a detailed explanation.

The user name is added to the Vboxusers group and can be resolved after restarting or logging off.

sudo adduser usrname vboxusers

　　The Fourth step: do not pull out the U disk, run the virtual system, in the "equipment" –> "Distribution USB Device", the U disk selected, and then you can use the U disk normally.