Can’t use the USB ports on Virtual Box

Hello,
I installed Virtual Box on a PC running with Windows 7. Unfortunately, I can't use the USB ports on the machine guest (Windows XP).
In the configuration of the virtual machine, I turned on the EHCI controller for USB 2.0, but when I add a USB device filter (+ button), UBS no device is available, while a USB Drive connected to the PC.
I tried everything I could read in the documentation of Virtual Box, but there must be an installation error somewhere.
I therefore appeal to you to find a solution.
Thank you.
