드라이버 서명안됨

https://support.microsoft.com/ko-kr/kb/976017

https://blogs.msdn.microsoft.com/matthew_van_eerde/2010/08/23/troubleshooting-how-to-install-the-microsoft-hd-audio-class-driver/

bcdedit /set loadoptions DDISABLE_INTEGRITY_CHECKS

bcdedit /set nointegritychecks OFF

bcdedit /set TESTSIGNING ON

서명 안된 드라이버 로드

Windows 7

- 부팅시 F8

Windows 8

F8 활성화 : bcdedit /set {default} bootmenupolicy legacy

F8 비활성화 : bcdedit /set {default} bootmenupolicy standard

Windows 10 

F8 활성화 : bcdedit /set {default} bootmenupolicy yes

F8 비활성화 : bcdedit /set {default} bootmenupolicy no

or

복구모드