ACCESS DENIED for Administrative tools (DSA.MSC + +)

I can’t open any administrative tool i.e. all of “.msc” extension with administrative user also.

I have checked the permision of that folder and files in “system32”, and its ok.

But I can access the same adding snap-in in console >>”MMC”>> and that is not allowing me to access the GROUP POLICY of any OU or GROUP from that sanp-in.

My Child domain is working fine.

Can any one tell me what is blocking me using the tools?