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Open the Registry Editor click on the Start button on your taskbar, then click on Run and type “regedit” and click on OK to start the regedit utility.

Expand HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control.

From there right click and create a new key and name it “StorageDevicePolicies”. In the window on the right then create a new DWORD value and label it WriteProtect, give it a value of “1″ and users can no longer write to USB drives. To re-enable this option change the value to 0 and users are again allowed to write.

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