No More Windows CD

To avoid the hassle of hunting down your Windows XP CD every time you want to
restore a system file (Windows File Protection at work) or add and remove components,
just copy the entire thing to your disk and modify a setting in the Group Policy Editor.
Navigate to Computer Configuration > Administrative Templates > System.
On the right-hand pane, you’ll find “Specify Windows installation file location”.
Double-click this, select Enable, and enter the path to your Windows XP setup file.
You can even point it to a network path on your office LAN, so you don’t have to run to your system admin every time Windows wants the installation CD.