SelectQuery Myquery = new SelectQuery("select name, FreeSpace from win32_logicaldisk where drivetype=3");
            ManagementObjectSearcher Drivesearcher = new ManagementObjectSearcher(Myquery);

            foreach (ManagementObject MObject in Drivesearcher.Get())
            {
                MessageBox.Show("Drive Name:"+MObject["name"].ToString()+"  "+"Free Space:" +MObject["FreeSpace"].ToString() );
                
            }