This thread on these forums deals specifically with denying access to any user the use of a USB Flash drive. I have the opposite problem.
In our environment we need to allow our researchers to use any USB flash drive on any of the shared equipment computers. The problem is that they are restricted users and cannot install software/drivers/devices. Many new ones work off the bat but sometimes there will be an odd device that asks you to install the default XP drivers, which requires an Administrator to come manually authorize it.
I’ve tried going the route of changing the local policy to allow all users to install devices and I’ve change the permissions on USBSTOR and corresponding inf files. I cannot for the life of me find any info that goes the opposite way of denying their use.