April 21, 2020—KB4550947 (OS Build 14393.3659)

IMPORTANT We have been evaluating the public health situation, and we understand this is impacting our customers. In response to these challenges, we are prioritizing our focus on security updates. Starting in May 2020, we are pausing all optional non-security releases (C and D updates) for all the supported versions of Windows client and server products (Windows 10, version 1909 down to Windows Server 2008 SP2).

There is no change to the monthly security updates (B release – Update Tuesday); these will continue as planned to ensure business continuity and to keep our customers protected and productive.

Reminder The additional servicing for Windows 10 Enterprise, Education, and IoT Enterprise editions ended on April 9, 2019 and doesn't extend beyond this date. To continue receiving security and quality updates, Microsoft recommends updating to the latest version of Windows 10.

Reminder March 12 and April 9 were the last two Delta updates for Windows 10, version 1607. For Long-Term Servicing Branch (LTSB) customers, 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 1607, reached end of service on April 10, 2018. Devices running Windows 10 Home or Pro 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.

IMPORTANTWindows 10 Enterprise and Windows 10 Education editions will receive additional servicing at no cost until April 9, 2019. Devices on the Long-Term Servicing Channels (LTSC) will continue to receive updates until October 2026 per the Lifecycle Policy page. Windows 10 Anniversary Update (v. 1607) devices running the Intel “Clovertrail” chipset will continue to receive updates until January 2023 per the Microsoft Community blog.

Windows Server 2016 Standard edition, Nano Server installation option and Windows Server 2016 Datacenter edition, Nano Server installation option reached end of service on October 9, 2018. These 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.

Windows 10 Mobile, version 1607, reached end of service on October 8, 2018. 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, and so on, please see the following article.

Highlights

Updates an issue with pasting mixed content of images and text from Microsoft Word into Internet Explorer.

Improvements and fixes

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

Addresses an issue with pasting mixed content of images and text from Microsoft Word into Internet Explorer.
Addresses an issue with Dynamic Data Exchange (DDE) that causes a memory leak when multiple clients connect to the same server.
Addresses an issue that causes new child windows to flicker and appear as white squares on server devices that are configured for stark visual contrast.
Addresses an issue that causes an error in logman.exe. The error is, "A user account is required in order to commit the current Data collector Set properties."
Addresses an issue that causes a memory leak in the LsaIso.exe process when the server is under a heavy authentication load and Credential Guard is enabled.
Addresses an issue that might cause a delay of up to two minutes when signing in or unlocking a session on Hybrid Azure Active Directory-joined machines.
Addresses an issue with running klist.exe that causes lsass.exe to stop working and generates an access violation error (0xC0000005).
Addresses an issue with merging Windows Defender Application Control policies that sometimes generates a duplicate rule ID error and causes the Merge-CIPolicy PowerShell command to fail.
Addresses an issue that might prevent Dynamic Host Configuration Protocol (DHCP) servers from providing the right options to clients when a reservation exists.
Addresses an issue that prevents Microsoft Internet Information Services (IIS) management tools, such as IIS Manager, from managing an ASP.NET application that has configured SameSite cookie settings in web.config.
Addresses an issue that causes devices that are provisioned for Windows Hello for Business (WHfB) to fail. Registration occasionally fails, which leads to a delay in WHfB enrollment and, in some instances, creates Conflicting Objects (CNF) in the Active Directory “Registered Device” container.
Addresses an issue that occurs when you try to sign in to Windows during recovery mode. The error, "No administrator accounts are available on this machine", appears.
Addresses an issue that prevents you from removing some local users from local built-in groups. For example, you cannot remove "Guest" from the "Guests" local group.
Addresses an issue that logs incorrect Internet Protocol (IP) addresses in the audit logs because of missing or old data for active requests coming from "windowstransport/usernamemixed/certificatemixed" endpoints.
Addresses an issue that might cause a deadlock in the Remote Desktop Gateway service.
Addresses an issue in Srv2.sys that might cause 0x18, 0xC2, and 0x19 errors.
Addresses an issue that prevents the Notification State registries from being deleted for certain apps even after the user profile is deleted.

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.

Known issues in this update

Symptom

Workaround

After installing KB4467684, the cluster service may fail to start with the error “2245 (NERR_PasswordTooShort)” if the group policy “Minimum Password Length” is configured with greater than 14 characters.

Set the domain default "Minimum Password Length" policy to less than or equal to 14 characters.

Microsoft is working on a resolution and will provide an update in an upcoming release.

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. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

If you are using Windows Update, the latest SSU (KB4550994) 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

Release Channel	Available	Next Step
Windows Update or Microsoft Update	Yes	Go to Settings > Update & Security > Windows Update and select Check for updates.
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.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4550947.

April 21, 2020—KB4550947 (OS Build 14393.3659)

Highlights

Improvements and fixes

Known issues in this update

How to get this update

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