How can I prevent users from connecting to a USB storage device?

USB storage device is already installed on the computer : set the Start value in the following registry key to 4: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStorWhen you do this, the USB storage device does not work when the user connects the device to the computer. To set the Start value, follow these steps:Click Start, and then click Run.In the Open box, type regedit, and then click OK.Locate and then click the following registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\UsbStorIn the details pane, double-click Start.In the Value data box, type 4, click Hexadecimal (if it is not already selected), and then click OK.Exit Registry Editor.
If a USB storage device is not already installed on the computer : When you do this, users cannot install a USB storage device on the computer. To assign a user or group Deny permissions to the Usbstor.pnf and Usbstor.inf files, follow these steps:Start Windows Explorer, and then locate the %SystemRoot%\Inf folder.Right-click the Usbstor.pnf file, and then click Properties.Click the Security tab.In the Group or user names list, add the user or group that you want to set Deny permissions for.In the Permissions for UserName or GroupName list, click to select the Deny check box next to Full Control.
Note Also add the System account to the Deny list.In the Group or user names list, select the SYSTEM account. In the Permissions for UserName or GroupName list, click to select the Deny check box next to Full Control, and then click OK. Right-click the Usbstor.inf file, and then click Properties.Click the Security tab.In the Group or user names list, add the user or group that you want to set Deny permissions for. In the Permissions for UserName or GroupName list, click to select the Deny check box next to Full Control.In the Group or user names list, select the SYSTEM account. In the Permissions for UserName or GroupName list, click to select the Deny check box next to Full Control, and then click OK.