Before you install this update, see the Prerequisites section. Note This update is re-released on October 13, 2015, with a smaller boot loader file bootmgfw.efi. When this issue occurs, applications that depend on TPM won't function until you reset the TPM lockout.

Run the following commands from an Administrator command prompt to restore the boot files in EFI system boot partition. Type each command separately and then press Enter:

Surface Unified Extensible Firmware Interface (UEFI) replaces the standard basic input/output system (BIOS) with new features including faster startup and improved security. You can use Surface UEFI to manage the firmware features on your Surface. These Surface models use the new firmware UEFI interface:

Fixes an issue in the Cdboot.efi, Cdboot_noprompt.efi, Efisys.bin, and Efisys_noprompt.bin files that causes a "Boot failed" error message. This issue occurs when you start a UEFI-enabled computer from the installation DVD of a 64-bit version of Windows 7 or Windows Server 2008 R2.

Learn how to enable virtualization through the UEFI (or BIOS) of your PC to run the Windows Subsystem for Android or Windows Subsystem for Linux.

Secure Boot is a security feature in Unified Extensible Firmware Interface (UEFI) based firmware that helps ensure that only trusted software runs during a device's boot (start) sequence.

Learn how to use Manage and Optimize Drives to keep your disk and data drives defragmented and at top performance in Windows.

To find information about restoring your device in this scenario, please visit the article, Windows Recovery Environment. These steps might look complicated at first glance, but following them in order, step-by-step, will help get you back on track. Sign in to the computer as an administrator.

Find out the steps you can take if you receive a message telling you a driver can't load on your device.

Learn how to use a health report in Windows Security to manage your device performance and keep your device secure.