/// The GetDriveType function determines whether a disk drive is a removable, fixed, CD-ROM, RAM disk, or network drive

  public static extern DriveType GetDriveType([MarshalAs(UnmanagedType.LPStr)] string lpRootPathName);

  Private Declare Function GetDriveType Lib "kernel32" _

  Alias "GetDriveTypeA" (ByVal lpRootPathName As String) As Integer

  public static extern DriveType GetDriveType([MarshalAs(UnmanagedType.LPTStr)] string lpRootPathName);

    public static extern DriveType GetDriveType([MarshalAs(UnmanagedType.LPStr)] string lpRootPathName);

        DriveType dt = GetDriveType("D:\\");//for me this is cdrom