Show hidden Device Windows XP

Hallo guys....If you have problem with Device Manager, you cant show Hidden Device....Try This Intruction.
This sollution Tested By me..

1. Right-click My Computer and select Properties
2. Click on the Advanced tab
3. Click on Environment Variables
4. Below the bottom Environment Variables window pane (System Variables), click on New
5. For Variable Name, enter devmgr_show_nonpresent_devices
6. For Variable Value, enter 1
7. Click OK to close Environment Variables and OK again to close System Properties 

Now that you have created this entry, when you open Device Manager, you can click on View and then select Show hidden devices from the menu. You can identify the hidden devices by their grayed-out icons.