In computer management, DIsk management is not accessable

Hi,

I have a problem i have seen in my friend’s PC, When i go to :

Right click on my computer> manage>disk management…..

It gives an error stating that disk management has been disabled by your administrator.

I am not able to recover the feature again… how does it happen? Is it due to a virus? How it can be recovered accept system restore utility in windows XP. OS being used is XP with SP2.
Is there any way to enable the feature through registry.