USB 3 on VirtualBox

I run win 7 in a virtual machine. it was not recognizing my usb 3 device (data traveler usb 3.0 stick), it was greyed out. I had to shut down the windows of the VM, then I switched to usb 3, still not working after restarting.
the intel usb 3 support should be installed in the win 7 (my virtual os) in this case to support usb 3
grab it here
https://downloadcenter.intel.com/download/21129/USB-3-0-Driver-Intel-USB-3-0-eXtensible-Host-Controller-Driver-for-Intel-7-Series-C216-Chipset-Family?product=65855

if you have a difference cpu (the cpu of the vm is the same as that of the host machine), then get it from the relevant page.

then usb was showing as attached to the virtual machine, but nothing happened in win 7 (no message or error, the usb started to show under diskpart list in cmd console)
simply open cmd console, type diskpart , list volumes

This second issue is because of ExFat format that I did on the host (not windows). Somehow the windows cannot recognize it. Now I had to use the clean command of diskpart:
first select the problematic disk:

select disk0
clean
if you still have issues, grab the usb and format it under another windows system, then insert it in the virtual machine and it will work.