Root access in windows 7/10

Question

Im having a bit of a challenge here. Im supposed to backup a computer, and therefore I would like to use c:\ as my origo for a recursive search for files to backup.

using System;
using System.IO;

class Program
{
  static void Main()
  {
    int i;
    string source   = @"c:\";
    string destin   = @"x:\";
    string[] TypeOfFiles = new string[14];
   i=0;
   // Images / Movies:
   TypeOfFiles[i]   = "jpg"; i++;
   TypeOfFiles[i]   = "gif"; i++; 
   TypeOfFiles[i]   = "png"; i++; 
   TypeOfFiles[i]   = "jpeg"; i++;  
   TypeOfFiles[i]   = "tif"; i++;
   TypeOfFiles[i]   = "tiff"; i++;
   TypeOfFiles[i]   = "bmp"; i++; 

   // Adobe
   TypeOfFiles[i]   = "pdf"; i++; 

   // Office Classic:    
   TypeOfFiles[i]   = "doc";  i++;
   TypeOfFiles[i]   = "xls"; i++;
   TypeOfFiles[i]   = "mdb";  i++;

   // Office New:   
   TypeOfFiles[i]   = "docx";  i++;
   TypeOfFiles[i]   = "xlsx";  i++;
   TypeOfFiles[i]   = "mdbx";  i++;

   for (int n = 0; n <= TypeOfFiles.GetUpperBound(0); n++)
   {
     string[] files = Directory.GetFiles("C:\\", "*." + TypeOfFiles[n], SearchOption.AllDirectories);
    foreach (string file in files)
    {
            Console.WriteLine(file);
      }
    }
  }
}

Im running the program from a console (as Administrator). I get this exception: Exception: System.UnauthorizedAccessException: Access to path 'C:\Documents and Settings' was denied. ved System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath) ved System.IO.FileSystemEnumerableIterator1.AddSearchableDirsToStack(SearchData localSearchData) ved System.IO.FileSystemEnumerableIterator1.MoveNext() ved System.Collections.Generic.List1..ctor(IEnumerable1 collection) ved System.IO.Directory.GetFiles(String path, String searchPattern, SearchOption searchOption) ved Program.Main()

I have also tried: net user administrator /active:yes

I need to access the root. Can anyone help me?