Many people seem to run into problems when they want to use USB devices in a virtual Windows environment. So let's help you out here: In this manual I assume you installed the latest version of Virtualbox AND that you installed the VirtualBox Extension Pack. If not: hurry to the virtualbox.org website ;-) and see you in a sec! To write this manual and re-create the following steps to be sure all steps were in the right order, I used a laptop with Ubuntu 16.04 64bit (OS), Virtualbox 5.1.14 (for Ubuntu), Expansion pack 5.1.14, and Windows 7 64bit (virtual).
1/ We start in Linux. If you didn't install the system tools already, execute the following command in the terminal:
sudo apt-get install gnome-system-tools
This will add the necessary tools to work with groups in Ubuntu.
Then search in the Dash for 'Users'
An icon with two unknown people will appear.. the description reads 'User and Groups'
Click on it!
In the panel click 'Manage Groups'
Search for 'vboxuser' in the 'Groups available on the system' panel
Then click 'Properties'
Add yourself (check box) to the group
Confirm with 'OK'
Then 'Close' the panel
And finally 'Close' the 'Users Settings' panel
2/ Great! From now on you can access all the attached USB devices in your virtual Win7 OS.
Start Virtualbox - select (highlight) the OS you installed (for Example Win7)
Click on 'SETTINGS'
Click on 'USB'
Check 'USB 2.0 (EHCI Controller' or 'USB 3.0 (xHCI Controller' if your machine has USB2 or USB3 ports which you would like to use in the virtual OS.
Click OK (and the window closes)
Now Start the OS
You may see a message (like in XP for example) that says
'Found new hardware - Universal Serial Bus (USB) Controller'. That's a good sign ;-)
Nog you're in the OS... don't forget to right-click on the 'USB stick icon' which you will see at the bottom on the right.
Select the stick you wish to use and there we go! ;-)
PS: the USB stick icon can be found between the icon with the two little screens and the icon with the little folder. Still not found? Really? At the bottom, on the right.. you will see 10 very small icons. Oh yes, it works Professor!