June 11, 2019—KB4503284 (OS Build 16299.1217)

**Reminder:**March 12 and April 9 will be the last two Delta updates for Windows 10, version 1709. 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.

Reminder: Windows 10, version 1709, will reach end of service on April 9, 2019 for devices running Windows 10 Home, Pro, Pro for Workstation, and IoT Core editions. These devices 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, Education, and IoT Enterprise editions will continue to receive servicing for 12 months at no cost per the lifecycle announcement on October 2018.

Improvements and fixes

This update includes quality improvements. Key changes include:

• Addresses a security vulnerability by intentionally preventing connections between Windows and Bluetooth devices that are not secure and use well-known keys to encrypt connections, including security fobs. If BTHUSB Event 22 in the Event Viewer states, “Your Bluetooth device attempted to establish a debug connection….”, then your system is affected. Contact your Bluetooth device manufacturer to determine if a device update exists. For more information, see CVE-2019-2102 and KB4507623.
• Addresses an issue that may prevent Internet Explorer 11 from opening if the Default Search Provider is not set or is malformed.
• Security updates to Microsoft Edge, Microsoft Scripting Engine, Internet Explorer, Windows App Platform and Frameworks, Windows Input and Composition, Windows Media, Windows Shell, Windows Server, Windows Authentication, Windows Datacenter Networking, Windows Storage and Filesystems, Windows Virtualization, Internet Information Services, and the Microsoft JET Database Engine.
  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.

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.
  When trying to expand, view, or create Custom Viewsin Event Viewer, you may receive the error, “MMC has detected an error in a snap-in and will unload it.” and the app may stop responding or close. You may also receive the same error when using Filter Current Login the Actionmenu with built-in views or logs. Built-in views and other features of Event Viewer should work as expected.| This issue is resolved in KB4503281.
  Devices may have issues connecting to some Storage Area Network (SAN) devices using Internet Small Computer System Interface (iSCSI) after installing this update. You may also receive an error in the Systemlog section of Event Viewerwith Event ID 43 from iScsiPrt and a description of “Target failed to respond in time for a login request.”| This issue is resolved in KB4509477.
  Devices that start up using Preboot Execution Environment (PXE) images from Windows Deployment Services (WDS) or System Center Configuration Manager (SCCM) may fail to start with the error “Status: 0xc0000001, Info: A required device isn’t connected or can’t be accessed” after installing this update on a WDS server.| This issue is resolved in KB4512494.

How to get this update

Before installing this updateMicrosoft strongly recommends you install the latest servicing stack update (SSU) for your operating system before installing the latest cumulative update (LCU). SSUs improve the reliability of the update process to mitigate potential issues while installing the LCU and applying Microsoft security fixes. For more information, see Servicing stack updates.If you are using Windows Update, the latest SSU (KB4500641) will be offered to you automatically. To get the standalone package for the latest SSU, search for it in the Microsoft Update Catalog.Install this updateThis update will be downloaded and installed automatically from Windows Update. To get the standalone package for this update, go to the Microsoft Update Catalog website.File informationFor a list of the files that are provided in this update, download the file information for cumulative update 4503284.