USB 3.0 Drive in VirtualBox on PopOS!

Update: I now use Boxes and highly recommend you to use that for running your virtual machines from my experience.

If you've been trying to access a USB 3.0 drive on a virtual machine using VirtualBox, here's the steps to solve the problem.

This was the error I received, you may also experience this after installing the VirtualBox Extension Pack:

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

Step 1:

You're going to have to open terminal (Super+T) in your host and add your user to the vboxusers group with the following command:

sudo usermod -a -G vboxusers $USER

Step 2:

Now restart your computer, some may suggest just logging out but that didn't work for me. Restart and once logged in, open terminal (Super+T) and run this command:

groups $USER

You should see vboxusers in the list.

Step 3:

Open VirtualBox and select your virtual machine, go to Settings and select USB:

You should now be able to add your USB 3.0 device:

Step 4:

If you try to start your virtual machine and your USB is visible once logged in, perfect! But if you encounter this: 

RTR3InitEx failed with rc=-1912 (rc=-1912)
The VirtualBox kernel modules do not match this version of VirtualBox. The installation of VirtualBox was apparently not successful. Executing
'/sbin/vboxconfig'
may correct this. Make sure that you do not mix the OSE version and the PUEL version of VirtualBox.
where: supR3HardenedMainInitRuntime what: 4 VERR_VM_DRIVER_VERSION_MISMATCH (-1912) - The installed support driver doesn't match the version of the user.

Optional Step:

You will want to check if virtualbox-dkms is installed, open terminal (Super+T) and run the command:

dpkg -l | grep virtualbox-dkms

If the answer is yes, then delete it and install dkms

sudo apt-get purge virtualbox-dkms && \
sudo apt-get install dkms

Now we have to rebuild the VirtualBox kernel modules:

sudo /sbin/vboxconfig 

Start VirtualBox, boot your virtual machine and log in. Your USB device should now be visible: