a.vecchio0
New member
- Joined
- Sep 1, 2026
- Messages
- 1
Hello,
I am experiencing an issue with my MSI Stealth GS66 12UGS, purchased in 2022. I am posting here in the hope that this is a known issue and that you may be able to provide instructions to get the laptop working again.
After turning the laptop on for the first time in about a month, I received the following message:
“Secure Boot Violation. Invalid signature detected. Check Secure Boot Policy in Setup.”
After clicking “OK,” the laptop entered the BIOS directly on the date and time settings page. The date and time were incorrect, as if the RTC/CMOS battery had died or the BIOS settings had been reset while the laptop was powered off.
After setting the correct date and time and disabling Secure Boot, the laptop was able to boot. However, the operating system was only visible on an external monitor connected through HDMI; the built-in laptop display was no longer detected or usable.
While trying to make Windows detect the internal display again, I installed some Windows updates and attempted to update the graphics drivers. Now, when I turn the laptop on, the “Secure Boot Violation” error appears again and takes me to the BIOS. After a few seconds in the BIOS, the screen turns off completely and remains black until I force the laptop to shut down and turn it on again. The keyboard backlight stays on until I force the shutdown.
Could this be caused by a failed RTC/CMOS battery, corrupted BIOS/Secure Boot settings, or an issue with the internal display/GPU? Is there a safe procedure I can follow to reset or restore the BIOS/EC settings without risking further damage?
I tried to boot the laptop from the EFI USB as suggested in some MSI FAQ and other threads but before I can select anything the monitor is black.
Thank you for any help.
I am experiencing an issue with my MSI Stealth GS66 12UGS, purchased in 2022. I am posting here in the hope that this is a known issue and that you may be able to provide instructions to get the laptop working again.
After turning the laptop on for the first time in about a month, I received the following message:
“Secure Boot Violation. Invalid signature detected. Check Secure Boot Policy in Setup.”
After clicking “OK,” the laptop entered the BIOS directly on the date and time settings page. The date and time were incorrect, as if the RTC/CMOS battery had died or the BIOS settings had been reset while the laptop was powered off.
After setting the correct date and time and disabling Secure Boot, the laptop was able to boot. However, the operating system was only visible on an external monitor connected through HDMI; the built-in laptop display was no longer detected or usable.
While trying to make Windows detect the internal display again, I installed some Windows updates and attempted to update the graphics drivers. Now, when I turn the laptop on, the “Secure Boot Violation” error appears again and takes me to the BIOS. After a few seconds in the BIOS, the screen turns off completely and remains black until I force the laptop to shut down and turn it on again. The keyboard backlight stays on until I force the shutdown.
Could this be caused by a failed RTC/CMOS battery, corrupted BIOS/Secure Boot settings, or an issue with the internal display/GPU? Is there a safe procedure I can follow to reset or restore the BIOS/EC settings without risking further damage?
I tried to boot the laptop from the EFI USB as suggested in some MSI FAQ and other threads but before I can select anything the monitor is black.
Thank you for any help.