How to Disable USB Storage function on Windows XP by registry.

This is a subject which causes headaches to many IT managers and supervisors from time to time. As spreading of viruses, illegal software and medias like mp3s, videos and commercial espionage (theft of company confidential information) is generally done by usbsticks or usb disks etc.

When using common sense, may be, the most civilized way of preventing the usage is by IT policy, but, as you are already aware, we humans use the human factor and try to bend the rules whenever possible. So the only solution is to actually disable the regarding service so that risks are prevented automatically. 

Well, the good news is, Microsoft was clever enough to create one service that can disable access to Usb storage without disabling access to other USb devices such as mouse, keyboard etc.

As I'm a lazy sod, I'm going to copy paste the information from a resource I like alot. The site is owned by Daniel Petri, and the original document can be found at www.petri.co.il
It is also explained at http://support.microsoft.com/kb/823732

There are actually 2 ways of disabling Usb Storage access in Windows XP:

1.  Registry 
2. GPO (Group Policy Object - Active Directory) 

 In this document I will explain how to do it via registry. I'll write the document on how to do it via GPO in my other how to's.

To block your computer's ability to use USB Removable Disks follow these steps:

1. Open Registry Editor.
2. In Registry Editor, navigate to the following registry key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\USBSTOR

1. Locate the following value (DWORD):

START and give it a value of 4. Note: As always, before making changes to your registry you should always make sure you have a valid backup. In cases where you're supposed to delete or modify keys or values from the registry it is possible to first export that key or value(s) to a .REG file before performing the changes.

1. Close Registry Editor. You do not need to reboot the computer for changes to apply.

Enable usage of USB Removable Disks

To return to the default configuration and enable your computer's ability to use USB Removable Disks follow these steps:

1. Go to the registry path found above.

1. Locate the following value: Start and give it a value of 3.