GetDriveType 傳回值的含義

UINT WINAPI GetDriveType(
  __in          LPCTSTR lpRootPathName
);
      

Return code Description 
DRIVE_UNKNOWN		未知
 The drive type cannot be determined.     
DRIVE_NO_ROOT_DIR 		可移動磁盤 
 The root path is invalid; for example, there is no volume is mounted at the path.    
DRIVE_REMOVABLE		U盤，軟碟
 The drive has removable media; for example, a floppy drive, thumb drive, or flash card reader.
DRIVE_FIXED		本地硬碟, 移動硬碟
 The drive has fixed media; for example, a hard drive or flash drive.
DRIVE_REMOTE		網絡磁盤
 The drive is a remote (network) drive.
DRIVE_CDROM		CD-ROM
 The drive is a CD-ROM drive.   
DRIVE_RAMDISK		RAM 磁盤
 The drive is a RAM disk.    
           

參考：

http://tech.ddvip.com/2008-11/122655500792166.html