June 26, 2019—KB4509477 (OS Build 16299.1239)

Qo‘llanadi: Windows 10, version 1709

Improvements and fixes


This update includes quality improvements. Key changes include:

  • Addresses an issue that may prevent devices from connecting to some Storage Area Network (SAN) devices using Internet Small Computer System Interface (iSCSI) after installing KB4499147. You may also receive an error in the System log section of Event Viewer with Event ID 43 from iScsiPrt and a description of “Target failed to respond in time for a login request.”

If you installed earlier updates, only the new fixes contained in this package will be downloaded and installed on your device.

Known issues in this update


Symptom Workaround
Certain operations, such as rename, that you perform on files or folders that are on a Cluster Shared Volume (CSV) may fail with the error, “STATUS_BAD_IMPERSONATION_LEVEL (0xC00000A5)”. This occurs when you perform the operation on a CSV owner node from a process that doesn’t have administrator privilege.

Do one of the following:

  • 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.
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 update

Microsoft 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 update

To download and install this update, go to Settings > Update & Security > Windows Update and select Check for updates.

To get the standalone package for this update, go to the Microsoft Update Catalog website.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4509477