Mac无法开机

Hi 249a,

Welcome to Apple Support Communities, we're glad to assist. What were you trying to do when you got that message? If you were trying to start your Mac, follow the steps here: If your Mac doesn't turn on 

Good luck.

That appear to be a standard message from Microsoft Windows.

If you used any Windows-native software that modifies the partition Map, it also clobbers the MacOS partition, and you will need to re-install MacOS.

Boot Camp Assistant is the only good way to install Windows on a Mac.

If you did ANYTHING with Windows software such as Run FDISK to examine the partition Map,

Then Windows will re-write the partition map, overwriting the MacOS partition information.

You must ERASE the ENTIRE device, by its immutable manufacturer device-name.

use the little 'View' menu to select "show all devices"

Language-specific support:

Apple Support Communities also offers the following language-specific sites:

Apple Support Communities - Chinese