You may want to block USB mass storage device to disallow the unauthorized use of pendrives or you may want to unblock USB mass storage device to get access (most of the case in college’s net lab). Well, this can be done by a simple registry tweak. Before doing so, I recommend taking a backup of the regustry because playing with registry can be harmful for your OS. Read (How to backup your windows registry). When you have backup the key :
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\USBSTOR proceed further.
To disable access
To enable access
Copy the required code to a text file and save it as *.reg file. Just open that file and information will be added to the registry.
Source : Thinkdigit Forum
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