作业系统：Windows 7专业版
Service Pack：Service Pack 1
发生问题频率：
是否有做Windows Update：有
问题内容：电脑自动升级为Win10，后来还原为Win7就变成盗版，
想重灌变回正版，但是却找不到如何将开机顺序优先选为CD-ROM，
下图为进入的选择画面，请问该如何设定?麻烦大家解答，谢谢大家
Launch CSM [Always}
Launch PXE OPROM [Legacy]
Launch Video OPROM [Legacy]
Boot Priority Order
1st Boot Device [HL-DT-ST DVDRAM GHM...]
2nd Boot Device [WDC WD10EZEX-21M2NA....]
3rd Boot Device [Removable Device]
4th Boot Device [LAN]
Hard Disk Drive Priority [Press Enter]
Optical Disk Drive Priority [Press Enter]
Removable Disk Drive Priority [Press Enter]
Network Device Priority [Press Enter]
Boot Menu [Enabled]
D2D Recovery [Enabled]
Quiet Boot [Enabled]
Halt On [All, but keyboard]