Operating System Loader Has No Signature . . . these steps resolved my issue: 1. On Startup, press F12 2. Reset Bios to default settings 3. Restart laptop 4. In Bios, select Boot Sequence menu 5. Manually ADD additional line with the name "Windows Boot Manager" 6. Select /EFI/BOOT/BOOTX64.EFI 7. Exit answer found at: www.reddit.com/.../
I get this error when booting up my 2-in-1. It was working fine just last night! Please help me. System Bios: 01.10.00 Service Tag: <ADMIN NOTE: Service tag removed per privacy policy> EPSA: Build 4304.09 UEFI ROM
Inspiron 13-7359: Windows 10, Operating System Loader has no signature. 
Incompatible with Secureboot. All bootable devices failed Secure Boot 
verification.