There is another way of enabling the direct way to enable the regedit. See if it works:
go to :
1. start menu
2. click on Run
3. Type Gpedit.msc
4. select "User Configuration"
5. select "Administrative Templates"
6. select "System"
7. Under "System", there should be an entry for "Prevent access to registry editing tools"
just double click on it and select the option disable
8. restart windows.

This trick should work also.Just try and let me know.