On a Windows 10 PC, Secure Boot can be enabled only when the machine starts Windows through UEFI firmware and the installation is compatible with Secure Boot. Because Windows 10 reached the end of standard support in October 2025, treat this as a legacy-system configuration task rather than a substitute for moving to a supported operating system.
Check the Windows 10 boot configuration first
- Press Windows+R, type msinfo32, and press Enter.
- In System Information, find BIOS Mode. It should report UEFI before you attempt to turn on Secure Boot.
- Find Secure Boot State and note whether it says On, Off, or Unsupported.
- Back up important files and locate the recovery key for BitLocker or Device Encryption if encryption is enabled.
- Restart the computer and enter its UEFI setup using the key or recovery method documented by the PC or motherboard manufacturer.
- Locate the Secure Boot control. Its location varies among manufacturers and can appear under Boot, Security, Authentication, or a similar section.
- Enable Secure Boot, save the firmware settings, and allow Windows 10 to start.
- Open msinfo32 again and confirm that Secure Boot State now reports On.
If BIOS Mode says Legacy
Do not simply change the firmware from Legacy or CSM to UEFI. A Windows installation prepared for legacy boot can stop starting after that change. Converting the system can involve the disk’s partition style and Windows boot files, so use documentation for the exact computer and make a verified backup before attempting a conversion.
If Secure Boot is unavailable
Older hardware may not support Secure Boot, and some firmware exposes the option only after CSM is disabled or the manufacturer’s default Secure Boot keys are restored. Do not download random key files or change unrelated firmware options to force the setting to appear.
Be prepared for an encryption recovery prompt
Changing firmware or boot-security settings can alter measurements used by BitLocker or Device Encryption. Keep the correct recovery key available before making the change so an unexpected recovery screen does not lock you out of the Windows installation.
Secure Boot does not make Windows 10 supported again
Secure Boot can still protect the startup chain on compatible Windows 10 hardware, but it does not provide the operating-system security updates that ended with standard Windows 10 support. For an Internet-connected PC, plan a move to supported Windows hardware and software.
Kermit Matthews is a freelance writer based in Philadelphia, Pennsylvania with more than a decade of experience writing technology guides. He has a Bachelor’s and Master’s degree in Computer Science and has spent much of his professional career in IT management.
He specializes in writing content about iPhones, Android devices, Microsoft Office, and many other popular applications and devices.