Error when trying to replace .exe.

[jackyj245]

Hey guys Quick question. I have never had this problem before when applying a nocd to a game, but i also just recently updated to windows vista so im thinking that is why. Anyway, the problem is i execute the .exe into the folder it should go into, then i get this error

! C:\Users\computer room\Desktop\grurct2cd.rar: Cannot create rct2.exe
! Access is denied.
! C:\Users\computer room\Desktop\grurct2cd.rar: Cannot create grurct2cd.nfo
! Access is denied.
! C:\Users\computer room\Desktop\grurct2cd.rar: No files to extract
it wont let me replace it. Help?