C# Access to the path 'C:\Documents and Settings\' is denied

I'm using a simple DirectoryInfo to grab all directories on the root on the C drive. However, I'm running under administrator and i'm getting the error of path access denied, below is the code that I am running. How do I resolve the issue of path access?

DirectoryInfo Dinfo = new DirectoryInfo(@"C:\");
DirectoryInfo[] directories = Dinfo.GetDirectories("*.*", SearchOption.AllDirectories);