Windows Desktop Update [RESOLVED]

I have noticed that on one of my PCs at work Windows Desktop Update (Active Desktop etc)
doesn't seem to be installed.

This is strange because it is a Windows 2000 machine and I thought WDU was preinstalled....

There isn't a "web" tab in the display settings and there is no
"Active Desktop" in the right-click menu of the desktop.

It has just been updgraded from IE5.0 to IE6.

Is there anyway (registry maybe?) that I can check to see if it there but just turned off!?
If it is turned off, how do I turn it on again?

Put a .JPG file as background. If the active desktop is diabled windows will ask if you want to enable it/

It says "Windows cannot display the wallpaper you selected. Choose different wallpaper"

It seems like it isn't installed.
How is that possible?

It could be that security policies have changed, the administrator can disable several options for the users of the network (Win 2000 hides them, whereas I think previous versions of Windows just disabled them).