Applies ToWindows Server 2016 Windows Server 2016 Essentials Windows Server 2016 Standard Windows 10 Windows 10, version 1511, all editions Windows 10, version 1607, all editions Windows Server 2012 R2 Datacenter Windows Server 2012 R2 Standard Windows Server 2012 R2 Essentials Windows Server 2012 R2 Foundation Windows 8.1 Enterprise Windows 8.1 Pro Windows 8.1 Windows Server 2012 Datacenter Windows Server 2012 Datacenter Windows Server 2012 Standard Windows Server 2012 Standard Windows Server 2012 Essentials Windows Server 2012 Foundation Windows Server 2012 Foundation Windows Server 2008 R2 Service Pack 1 Windows Server 2008 R2 Datacenter Windows Server 2008 R2 Enterprise Windows Server 2008 R2 Standard Windows Server 2008 R2 Web Edition Windows Server 2008 R2 Foundation Windows 7 Service Pack 1 Windows 7 Ultimate Windows 7 Enterprise Windows 7 Professional Windows 7 Home Premium Windows 7 Home Basic Windows 7 Starter

Summary

Microsoft has released a Microsoft security advisory about this issue for IT professionals. The security advisory contains additional security-related information. To learn more about the vulnerability, see Microsoft security advisory (4010323): SHA-1 deprecation for SSL/TLS certificates.

More Information

Important

  • All future security and non-security updates for Windows 8.1, and Windows Server 2012 R2 require update 2919355 to be installed. We recommend that you install update 2919355 on your Windows 8.1-based, or Windows Server 2012 R2-based computer so that you receive future updates.

  • 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.

How to obtain and install the update

Method 1: Windows Update

This update is available through Windows Update. When you turn on automatic updating, this update will be downloaded and installed automatically. For more information about how to turn on automatic updating, see Get security updates automatically.  

This fix is included in the following updates:

May 9, 2017—KB4019215 (OS Build .001) May 9, 2017—KB4019264 (OS Build .002) May 9, 2017—KB4019474 (OS Build .001) May 9, 2017—KB4019472 (OS Build .002) May 9, 2017—KB4016871 (OS Build .002) May 9, 2017—KB4019473 (OS Build .001) May 9, 2017—KB4019214 (OS Build .002) May 9, 2017—KB4019263 (OS Build .002) May 9, 2017—KB4019213 (OS Build .002) May 9, 2017—KB4019216 (OS Build .003)

More Information

Help for installing updates: Support for Microsoft Update Security solutions for IT professionals: TechNet Security Troubleshooting and Support Help for protecting your Windows-based computer from viruses and malware: Virus Solution and Security Center Local support according to your country: International Support

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