July 9, 2019—KB4507450 (OS Build 15063.1928)

**Reminder:**March 12 and April 9 will be the last two Delta updates for Windows 10, version 1703. Security and quality updates will continue to be available via the express and full cumulative update packages. For more information on this change please visit our blog.

Windows 10, version 1703, reached end of service on October 8, 2018_. Devices running Windows 10 Home, Pro, Pro for Workstation, and IoT Core editions will no longer receive monthly security and quality updates that contain protection from the latest security threats. To continue receiving security and quality updates, Microsoft recommends updating to the latest version of Windows 10._**IMPORTANT:**Windows 10 Enterprise and Windows 10 Education editions will receive one year of additional servicing at no cost.

Windows 10 Mobile, version 1703, reached end of service on June 11, 2019. Devices running Windows 10 Mobile and Windows 10 Mobile Enterprise will no longer receive monthly security and quality updates that contain protection from the latest security threats. To continue receiving security and quality updates, Microsoft recommends updating to the latest version of Windows 10.

For more information about the various types of Windows updates, such as critical, security, driver, service packs, etc., please see the following article.

**July 19, 2019 - IMPORTANT:**Beginning with the July 2019 updates, Active Directory domain controllers will intentionally block unconstrained delegation across forest, external, and quarantined trusts. Authentication requests for services that use unconstrained delegation over the listed trust types will fail when you request new tickets. Administrators should reconfigure the affected services to use resource-based constrained delegation. For more information, see KB4490425.

Highlights

• Updates an issue with BitLocker encryption recovery mode.
• Updates to improve security when using Internet Explorer, Microsoft Edge, wireless technologies, and Microsoft Office products.

Improvements and fixes

This update includes quality improvements. Key changes include:

• Provides protections against a variant (CVE-2019-1125) of the Spectre Variant 1 speculative execution side channel vulnerability.
• Addresses an issue that may cause BitLocker to go into recovery mode if BitLocker is being provisioned at the same time as updates are being installed.
• Addresses an issue that may cause some devices with Hyper-V enabled to enter BitLocker recovery mode and receive the error, “0xC0210000”.
• Security updates to Windows Server, Microsoft Scripting Engine, Windows Storage and Filesystems, Microsoft Graphics Component, Windows Input and Composition, Windows Virtualization, Windows App Platform and Frameworks, Windows Kernel, Internet Explorer, and Microsoft Edge.
  If you installed earlier updates, only the new fixes contained in this package will be downloaded and installed on your device.For more information about the resolved security vulnerabilities, please refer to the Security Update Guide.

Windows Update ImprovementsMicrosoft has released an update directly to the Windows Update client to improve reliability. Any device running Windows 10 configured to receive updates automatically from Windows Update, including Enterprise and Pro editions, will be offered the latest Windows 10 feature update based on device compatibility and Windows Update for Business deferral policy. This doesn’t apply to long-term servicing editions.

Known issues in this update

• Perform the operation from a process that has administrator privilege.
• Perform the operation from a node that doesn’t have CSV ownership.
  Microsoft is working on a resolution and will provide an update in an upcoming release.
  After installing this update, opening or using the Window-Eyes screen reader app may result in an error and some features may not function as expected.Note Users who have already migrated from Window-Eyes to Freedom Scientific’s other screen reader, JAWS, should not be affected by this issue.| This issue is resolved in KB4507467.

How to get this update