Configuring USB Settings in Oracle VirtualBox

Learn how to enable a VirtualBox USB controller, attach host USB devices to a guest, verify detection, and safely switch device ownership.

Oracle VM VirtualBox can make a physical USB device connected to the host operating system available to a virtual machine (VM). This feature is called USB passthrough. The guest operating system communicates with the device through a USB controller that VirtualBox presents as virtual hardware.

The USB settings belong to one selected VM. They do not change the physical USB controller configuration of the host computer.

Key USB and VirtualBox terms

Oracle VM VirtualBox Manager: The main VirtualBox interface used to select VMs and open their configuration settings.
Virtual machine: A software-defined computer that runs a guest operating system.
Host operating system: The operating system installed on the physical computer running VirtualBox.
Guest operating system: The operating system installed inside the VM.
USB controller: Virtual hardware presented to the guest that enables USB communication.
USB passthrough: The process of making a host-connected USB device directly available to a guest VM.
Settings dialog: The per-VM configuration window in VirtualBox.
Powered-off state: A completely shut-down VM state in which hardware settings can normally be modified safely.
Saved state: A suspended VM condition that preserves the VM's current session and is different from a complete shutdown.
Device driver: Guest operating system software that allows the guest to communicate with a hardware device.

What the USB settings control

The USB category in a VM's Settings dialog controls whether USB support is available to that guest. When enabled, VirtualBox supplies a virtual USB controller. The guest sees and uses that virtual controller; it does not receive the host's complete hardware configuration.

A physical device follows this general path:

The device is connected to the physical computer and initially belongs to the host operating system.
VirtualBox assigns the device to a running VM through its USB device-selection workflow.
The guest communicates with the device through the VirtualBox USB controller.
The guest uses its own suitable device driver to recognize and operate the device.

While the device is assigned to the guest, it may be unavailable to host applications. This is expected exclusive-access behavior, especially for removable storage.

Default USB controller behavior

Newly created VMs typically include a USB controller by default. However, verify the controller state when a USB device is unavailable, when working with an older VM configuration, or after importing or modifying a VM.

Enabling the controller alone does not automatically make every host USB device appear in the guest. The controller must be enabled, and the particular device must also be attached to the running VM.

Prerequisite: fully power off the VM

Shut down the guest operating system completely before changing the VM's USB controller configuration. A running VM is actively using its virtual hardware, so hardware changes may be unavailable or inappropriate.

Powered off: The guest has shut down and the VM is not running. This is the preferred state for changing controller settings.
Paused: VM execution is temporarily suspended, but the VM session still exists. This is not the same as powering off.
Saved state: VirtualBox has stored the VM's current session so it can resume later. This is also not a complete shutdown.

If the VM is paused or saved, resume it and shut down the guest normally when possible. If a saved state prevents configuration changes, resolve or discard that state only when appropriate; discarding it loses the suspended session's unsaved runtime state.

Open the USB settings page

Open Oracle VM VirtualBox Manager.
Select the target VM. Check its name carefully so you do not change another VM's hardware configuration.
Confirm that the target VM is fully powered off.
Open the VM's Settings dialog.
Select the USB category.

Enable a USB controller

In the USB settings page, locate Enable USB Controller.
Select the option if it is not already enabled.
Use the dialog's confirmation control, such as OK, to save the configuration.
Start the VM after the change has been applied.

Use the settings window's confirmation control rather than closing it without saving. The USB controller is now available to the guest, but individual USB devices still need to be attached when required.

Step	Action in VirtualBox	Expected Result
Power off the VM	Shut down the guest completely	The VM is neither running, paused, nor in a saved state
Open VM Settings	Select the correct VM in VirtualBox Manager and open Settings	The per-VM configuration dialog appears
Select USB	Choose the USB category	USB controller options are displayed
Enable USB Controller	Select the controller option	Virtual USB hardware is enabled for the guest
Save settings	Confirm the change with the dialog's confirmation control	The configuration is stored for the selected VM
Start and verify the guest	Start the VM and inspect its device-management tools	The guest can detect the controller and an attached USB device

Attach a host-connected USB device to the guest

Connect the USB device to the host computer.
Make sure the VM's USB controller is enabled. Change that setting only while the VM is powered off.
Start the VM.
Use the applicable VirtualBox VM device-selection workflow to attach the USB device to the guest. Depending on the VirtualBox version and desktop interface, this is available through the VM window's device menu or USB device control.
Wait for the guest to detect the device before opening files or starting other operations.

Attaching a device transfers its active ownership from the host to the guest for the duration of the attachment. Host applications may no longer be able to read or write the device. The guest must have a compatible device driver; enabling USB support does not install drivers inside the guest.

Verify USB availability in the guest

Confirm that the VM is running after the controller was enabled.
Attach an appropriate, low-risk USB device, such as removable storage where permitted.
Open the guest operating system's device-management tool.
Check that the USB controller or attached device is recognized without a driver error.
Perform a small test, such as viewing the removable device, without immediately modifying important data.

If the controller appears but the device does not, check whether the physical device is actually assigned to the guest and whether the guest has the required driver.

Host and guest responsibilities

Component	Responsibility	What to Verify
Host operating system	Detects the physically connected USB device and may hold it before passthrough	The device is connected, not disabled, and not being held by an important host operation
VirtualBox virtual machine configuration	Provides the virtual USB controller for the selected VM	The correct VM is powered off while configured and its USB controller is enabled
Guest operating system	Loads drivers and communicates with the passed-through device	The device or controller appears in the guest's device-management tools
Physical USB device	Provides the storage, input, or other USB function	The device is connected securely and is detached safely before ownership changes

Example: enable USB support for an existing VM

Shut down the target guest operating system completely.
In VirtualBox Manager, select the target VM.
Open Settings, then choose USB.
Enable Enable USB Controller.
Confirm and save the configuration.
Start the VM.
Check the guest's device-management tools and test an appropriate USB device.

Example: make USB storage available to the guest

Connect the storage device to the host.
With the VM powered off, enable its USB controller in Settings > USB.
Start the VM.
Attach the storage device to the guest through the applicable VirtualBox USB device-selection workflow.
Confirm that the guest detects the device before accessing its files.
When finished, unmount or eject the storage device from the guest.
Detach it from the VM before using it again on the host.

Troubleshooting USB problems

The USB controller option cannot be changed

Check whether the VM is running, paused, or in a saved state.
Shut down the guest fully and reopen its Settings dialog.
If a saved state continues to block the change, resolve or discard the saved state only after considering the loss of the suspended session.

The device is visible on the host but not in the guest

Power off the VM and confirm that the USB controller is enabled.
Start the VM and explicitly assign or reconnect the device to the guest.
Check the guest's device-management tools for recognition or driver errors.
Install or repair the suitable guest device driver when required.
Close host applications that may be using the device.

USB storage becomes unavailable on the host

The device may currently be passed through to the guest. This is normal while the guest owns the device. Safely unmount or eject it in the guest, detach it from the VM, and then allow the host to use it.

Data access errors appear after switching ownership

Use the guest's safe removal or unmount procedure before detaching storage.
Avoid switching ownership during file transfers or other active write operations.
If unsafe removal already occurred, check the file system for errors before continuing to use the device.

Safe configuration checklist

Confirm that you selected the correct VM before editing settings.
Fully shut down the VM before changing its USB controller configuration.
Save the Settings dialog before launching the guest.
Remember that enabling the controller and attaching a particular device are separate actions.
Ensure the guest has a suitable device driver.
Safely eject or unmount storage before returning it to host use.
Never disconnect USB storage while the guest is actively writing data.