September 21, 2021—KB5005624 (OS Build 18363.1830) Preview

^{UPDATED 9/21/2021} REMINDER Starting in October 2021, there will no longer be optional, non-security releases (known as "C" releases) for Windows 10, version 1909. Only cumulative monthly security updates (known as the "B" or Update Tuesday release) will continue for Windows 10, version 1909. This September 21, 2021 update is the final non-security release for Windows 10, version 1909.

^6/15/21 IMPORTANT This release includes the Flash Removal Package. Taking this update will remove Adobe Flash from the machine. For more information, see the Update on Adobe Flash Player End of Support.

^11/19/20 For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types. To view other notes and messages, see the Windows 10, version 1909 update history home page.

Note Follow @WindowsUpdate to find out when new content is published to the release information dashboard.

Highlights

Updates an issue that causes the system time to be incorrect by one hour after a daylight saving time (DST) change.
Updates an issue with resizing images that might cause flickering and residual line artifacts.
Updates an issue that causes blurry News and interests icons when you use certain screen resolutions.
Updates an issue that prevents you from providing input to apps when the taskbar is not at the bottom of the screen.
Updates an issue that causes News and interests to appear when you right-click the taskbar even when you have turned off News and interests on your device.

Improvements and fixes

This non-security update includes quality improvements. Key changes include:

Addresses an issue that causes the system time to be incorrect by one hour after a daylight saving time (DST) change.
Provides administrators the option to reset the zoom to the default for HTML dialogs in Microsoft Edge Internet Explorer mode.
Addresses an issue with Enterprise Mode Site List redirection from Internet Explorer 11 to Microsoft Edge. In certain circumstances, the redirection opens a site in multiple tabs in Microsoft Edge.
Addresses an issue that fails to keep the NumLock state after a Fast Startup restart.
Addresses an issue with resizing images that might cause flickering and residual line artifacts.
Addresses an issue that always reports the update build revision (UBR) as zero (0) on a device during enrollment to mobile device management (MDM) service.
Removes the limitation of 25 maximum Traffic Selectors in the Windows native Internet Key Exchange (IKE) client and server.
Addresses an issue that causes a memory leak in lsass.exe when the pTokenPrivileges buffer is not released.
Addresses an issue with a non-paged pool (NPP) leak from the UxSF pool tag. This leak occurs when lsass.exe stops processing asynchronous Security Support Provider Interface (SSPI) calls.
Addresses an issue that prevents the xhunter1.sys driver from loading. As a result, some games cannot run when you enable Hypervisor-Protected Code Integrity (HVCI).
Addresses an issue that causes Windows to stop working if you deploy a Code Integrity policy without user mode rules.
Improves the performance of MsSense.exe in environments with User Datagram Protocol (UDP) applications that require high amounts of bandwidth.
Addresses an input method editor (IME) mode instability in the RemoteApp scenario. You must install this update on the Remote Desktop server and Remote Desktop client.
Addresses an issue that causes blurry News and interests icons when you use certain screen resolutions.
Addresses a paged pool memory leak of the registry keys for the Virtual Desktop ID that occurs in explorer.exe.
Addresses an issue that causes LogonUI.exe to stop working because Direct Manipulation fails to start.
Addresses an issue that causes apps to lose focus when the taskbar is not at the bottom of the screen.
Addresses an issue that causes News and interests to appear in the context menu even when you have disabled it on a device.
Addresses an issue that causes the LsaLookupSids() function to fail. This occurs when there are security identifiers (SID) for users that no longer exist in a group that contains cross-domain trusted users.
Implements a Group Policy setting for the following registry value:

Registry location: HKLM\Software\Policies\Microsoft\Windows NT\Printers\PointAndPrint

Value name: RestrictDriverInstallationToAdministrators

Value data: 1

For more information, see KB5005652.
Adds the ability to configure period or dot (.) delimited IP addresses interchangeably with fully qualified host names in the following Group Policy settings:
- Package Point and Print - Approved Servers
- Point and Print Restrictions
Addresses a known issue that might prevent devices from downloading and installing printer drivers when the devices attempt to connect to a network printer for the first time. We have observed this issue on devices that access printers using a print server that uses HTTP connections.

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

Windows Update Improvements

Microsoft 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.

Windows 10 servicing stack update - 18363.1790

This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) ensure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates.

Known issues in this update

Symptom	Workaround
After installing KB5005566, installation of printers using Internet Printing Protocol (IPP) might not complete successfully. Devices which had connected to and installed the printer prior to the installation of KB5005566 are unaffected and print operations to that printer will succeed as usual. Note IPP is not commonly used by devices designed for home use. The printing environments affected by this issue are more commonly found in enterprises and organizations.	This issue is resolved in KB5007189.
After installing this update on a print server, printing properties defined on that server might not be correctly provided to clients. Note this issue is specific to print servers and does not impact standard network printing. This issue will not cause printing operations to fail, however, custom settings defined on the server – for example, duplex print settings – will not be applied automatically, and clients will print with default settings only. This issue results from an improper building of the data file which contains the printer properties. Clients which receive this data file will not be able to use the file content and will instead proceed with default printing settings. Clients who have previously received the settings package prior to the installation of KB5005624 are unaffected. Servers which use default print settings and have no custom settings to provide to clients are unaffected. Note The printer connection methods described in this issue are not commonly used by devices designed for home use. Printing environments affected by this issue are more commonly found in enterprises and organizations.	This issue is resolved in KB5006667.
After installing this update, you might receive a prompt for administrative credentials every time you attempt to print in environments in which the print server and print client are in different times zones. Note The affected environments described in this issue are not commonly used by devices designed for home use. The printing environments affected by this issue are more commonly found in enterprises and organizations.	This issue is resolved in KB5006667.

Symptom

Workaround

After installing KB5005566, installation of printers using Internet Printing Protocol (IPP) might not complete successfully. Devices which had connected to and installed the printer prior to the installation of KB5005566 are unaffected and print operations to that printer will succeed as usual.

Note IPP is not commonly used by devices designed for home use. The printing environments affected by this issue are more commonly found in enterprises and organizations.

This issue is resolved in KB5007189.

After installing this update on a print server, printing properties defined on that server might not be correctly provided to clients. Note this issue is specific to print servers and does not impact standard network printing. This issue will not cause printing operations to fail, however, custom settings defined on the server – for example, duplex print settings – will not be applied automatically, and clients will print with default settings only.

This issue results from an improper building of the data file which contains the printer properties. Clients which receive this data file will not be able to use the file content and will instead proceed with default printing settings. Clients who have previously received the settings package prior to the installation of KB5005624 are unaffected. Servers which use default print settings and have no custom settings to provide to clients are unaffected.

Note The printer connection methods described in this issue are not commonly used by devices designed for home use. Printing environments affected by this issue are more commonly found in enterprises and organizations.

This issue is resolved in KB5006667.

After installing this update, you might receive a prompt for administrative credentials every time you attempt to print in environments in which the print server and print client are in different times zones.

Note The affected environments described in this issue are not commonly used by devices designed for home use. The printing environments affected by this issue are more commonly found in enterprises and organizations.

This issue is resolved in KB5006667.

How to get this update

Before installing this update

Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). SSUs improve the reliability of the update process to mitigate potential issues while installing the LCU. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

Prerequisite:

You must install the July 13, 2021 SSU (KB5004748) before installing the LCU.

Install this update

Release Channel	Available	Next Step
Windows Update or Microsoft Update	Yes	Go to Settings > Update & Security > Windows Update. In the Optional updates available area, you’ll find the link to download and install the update.
Windows Update for Business	No	None. These changes will be included in the next security update to this channel.
Microsoft Update Catalog	Yes	To get the standalone package for this update, go to the Microsoft Update Catalog website.
Windows Server Update Services (WSUS)	No	You can import this update into WSUS manually. See the Microsoft Update Catalog for instructions.

If you want to remove the LCU

To remove the LCU after installing the combined SSU and LCU package, use the DISM/Remove-Package command line option with the LCU package name as the argument. You can find the package name by using this command: DISM /online /get-packages.

Running Windows Update Standalone Installer (wusa.exe) with the /uninstall switch on the combined package will not work because the combined package contains the SSU. You cannot remove the SSU from the system after installation.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 5005624.

For a list of the files that are provided in the servicing stack update, download the file information for the SSU - version 18363.1790.

September 21, 2021—KB5005624 (OS Build 18363.1830) Preview

Highlights

Improvements and fixes

Windows 10 servicing stack update - 18363.1790

Known issues in this update

How to get this update

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