If MOF is deleted...

Dear all,

I'm fresh to MDR, and when I played it, I made a mistake that I deleted 
the node "MOF"
in the MDR browser, and then I cannot restore it any more. I've tried to 
deinstall
whole software NetbeansIDE, to re-install and to download MDR explorer 
with update center again, but the item of MDR explorer in update center 
has not been activated any more.

How should I do in order to have MOF in the MDR explorer again?

Thanks in advance.
Regards!

Bin