Accessing Denied Hidden Folder

I had hidden a folder named "z" in the hard drive "G" using command prompt like
G:>attrib +h +s +a +r z. After I used command prompt like G:>cacls z /p everyone:n
And it opens by the command G:>cacls z /p everyone:f and then G:>attrib -h -s -a -r z.
I had problems in my Windows so i had to reinstall Windows..
I installed Windows XP. And then when i tried to access that hidden folder, it is showing ACCESS DENIED.. Please help me out i am in a big problem.