Using Directory.Exists on a network folder when the network is down
bool pathExists = Directory.Exists(path);

Func<bool> func = () => Directory.Exists(path);
Task<bool> task = new Task<bool>(func);
task.Start();
if (task.Wait(100)) {
  return task.Value;
} else {
  // Didn't get an answer back in time be pessimistic and assume it didn't exist
  return false;
}

public static  bool DirectoryExists(string path)
    {

      try
      {
        if(System.IO.Directory.GetDirectories(path).Length>0)
        return true;
      }
      catch(Exception exp)
      {
      }
      return false;    }

[DllImport("WININET", CharSet = CharSet.Auto)]
    static extern bool InternetGetConnectedState(ref int lpdwFlags, int dwReserved);

    public static bool Connected
    {
        get
        {
            int flags = 0;
            return InternetGetConnectedState(ref flags, 0);
        }
    }

public static bool FolderExists(string directory)
    {
        if (new Uri(directory, UriKind.Absolute).IsUnc && !Connected)
            return false;
        return System.IO.Directory.Exists(directory);
    }