About this update
On Windows 8.1 and Windows Server 2012 R2, Microsoft will sometimes release a security update that blacklists a vulnerable boot manager to prevent the boot manager from being used maliciously. This update fixes an issue in the Secure Boot Advanced Installer (securebootai.dll) to prevent blacklisting the boot manager in use on the system that would make the system unbootable.
How to get this update
Important If you install a language pack after you install this update, you must reinstall this update. Therefore, we recommend that you install any language packs that you need before you install this update. For more information, see Add language packs to Windows.
Method 1: Windows UpdateThis update is available on Windows Update. For more information on how to run Windows Update, see How to get an update through Windows Update.
Method 2: Microsoft Download CenterThe following files are available for download from the Microsoft Download Center:
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base:
|All supported x86-based versions of Windows 8.1||Download the package now.|
|All supported x64-based versions of Windows 8.1||Download the package now.|
|All supported x64-based versions of Windows Server 2012 R2||Download the package now.|
119591 How to obtain Microsoft support files from online servicesMicrosoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.
Update detail information
PrerequisitesTo apply this update, you must have April 2014 update rollup for Windows RT 8.1, Windows 8.1, and Windows Server 2012 R2 (2919355) installed in Windows 8.1 or Windows Server 2012 R2.
Registry informationTo apply this update, you don't have to make any changes to the registry.
Restart requirementYou may have to restart the computer after you apply this update.
Update replacement informationThis update replaces the previously released update 3021910.
Removal informationAfter you install this servicing stack update, you can't uninstall it to revert to an earlier version of servicing stack update.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.