Microsoft has released new updates for Windows 10, version 1903, Windows Server version 1903, Windows 10, version 1909, Windows 10, version 1803, Windows 10, version 1809, Windows Server version 1809, Windows Server 2019, Windows 10, version 1607, Windows Server 2016, Windows 8.1, Windows Server 2012 R2, and Windows Embedded 8.1 Industry Enterprise.

April 21, 2020—KB4550945 (OS Builds 18362.815 and 18363.815)

Applies to: Windows 10, version 1903, all editions, Windows Server version 1903, Windows 10, version 1909, all editions

Highlights

• Updates an issue that prevents certain apps from opening after you upgrade from a previous version of Windows, and a Bad Image error message appears. 
• Updates in an issue that turns off notifications for devices that use a virtual private network (VPN) on a cellular network. 
• Updates an issue that prevents you from resuming a Microsoft Xbox game on a Windows device after upgrading from a previous version of Windows. 
• Updates an issue that causes a text box that contains multiple lines of text to stop responding in certain scenarios. 
• Updates an issue that generates unexpected notifications when you change the default application settings. 
• Updates an issue that causes Windows Update to stop responding when you check for updates. 
• Updates an issue that fails to print content that is outside of the margins of a document.

Improvements and fixes

Windows 10, version 1909

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

• This build includes all the improvements from Windows 10, version 1903.
• No additional issues were documented for this release.

Windows 10, version 1903

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

• Addresses an issue that prevents certain apps from opening after you upgrade from a previous version of Windows, and a Bad Image exception dialog box appears. 
• Addresses in an issue that turns off notifications for devices that use a virtual private network (VPN) on a cellular network. 
• Addresses an issue that prevents you from resuming a Microsoft Xbox game on a Windows device after upgrading from a previous version of Windows. 
• Addresses an issue that causes a box that contains multiple lines of text to stop responding in certain scenarios. 
• Addresses an issue that prevents the touch keyboard from appearing during sign in when the user is prompted for the password. 
• Addresses an issue that prevents the touch keyboard from opening in Universal Windows Platform (UWP) apps when USB devices are connected. 
• Addresses an issue that displays incorrect folder properties in File Explorer when the path is longer than MAX_PATH. 
• Addresses an issue that prevents the correct lock screen from appearing when all of the following are true:
  • The Group Policy Object (GPO) policy "Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\Interactive Logon: Do not require Ctrl+Alt+Del Computer" is disabled.
  • The GPO policy “Computer Configuration\Administrative Templates\System\Logon\Turn off app notifications on the lock screen” is enabled.
  • The registry key HKLM\SOFTWARE\Policies\Microsoft\Windows\System\DisableLogonBackgroundImage is set to 1.
• Addresses an issue that generates unexpected notifications related to changing the default application settings. 

• Addresses an issue that causes the sign in screen to be blurry. 
• Addresses an issue that causes Windows Update to stop responding when you check for updates. 
• Addresses an issue that prevents the Sign in options page from opening using the ms-settings:signinoptions-launchfingerprintenrollment Uniform Resource Identifier (URI). 
• Addresses an issue with Bluetooth group policy settings on Microsoft Surface Pro X devices. 
• Addresses an issue that causes a KERNEL_SECURITY_CHECK_FAILURE (139) stop error when Windows resumes from Sleep and turns on certain Bluetooth headsets. 
• Addresses a reliability issue in WDF01000.sys. 
• 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 prevents users from setting the REG_EXPAND_SZ keys in some automated scenarios. 
• 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 causes the Trusted Platform Module (TPM) initialization to fail with system event error 14 and prevents Windows from accessing the TPM. 
• Addresses an issue that causes communication with the TPM to time out and fail. 
• Addresses an issue that prevents hash signing using the Microsoft Platform Crypto Provider for TPMs from working correctly. This issue might also affect networking software, such as VPN applications. 
• Addresses an issue that prevents applications running in an Azure Active Directory environment from receiving account change notifications. This occurs when using the Web Account Manager (WAM) and the WebAccountMonitor API. 
• Addresses an issue that causes systems to stop working with a 0x3B stop code when running a binary that is signed by a revoked certificate. 
• 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 prevents a user’s PIN from being changed after connecting the device to Microsoft Workplace Join. 
• Addresses an issue that fails to print content that is outside of the margins of a document.
• 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 Microsoft Edge to stop working if you attempt to use paste functionality on webpages when cut-and-paste functionality has been disabled using a policy and Windows Defender Application Guard is active.
• Addresses an issue that causes the Clipboard service to unexpectedly stop working when signing out.
• Addresses an issue that displays a black screen to Windows Virtual Desktop users when they attempt to sign in.

April 21, 2020—KB4550945 (OS Builds 18362.815 and 18363.815)

April 21, 2020—KB4550944 (OS Build 17134.1456)

Applies to: Windows 10, version 1803, all editions

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 that occurs when a third-party application loads hidden tabs into Internet Options. 
• Addresses an issue with pasting mixed content of images and text from Microsoft Word into Internet Explorer. 
• Addresses an issue that prevents the first key stroke from being recognized correctly in the DataGridView cell. 
• 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 prevents users from setting the REG_EXPAND_SZ keys in some automated scenarios. 
• 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 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 prevents applications running in an Azure Active Directory environment from receiving account change notifications. This occurs when using the Web Account Manager (WAM) and the WebAccountMonitor API. 
• Addresses a Task Manager CPU frequency display issue that locks to the base frequency on devices equipped with certain CPUs. 
• 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 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 prevents certain apps from installing if they are published using a Group Policy Object.
• Addresses an issue that causes Microsoft Edge to stop working if you attempt to use paste functionality on webpages when cut-and-paste functionality has been disabled using a policy and Windows Defender Application Guard is active.

April 21, 2020—KB4550944 (OS Build 17134.1456)

April 21, 2020—KB4550969 (OS Build 17763.1192)

Applies to: Windows 10, version 1809, all editions, Windows Server version 1809, Windows Server 2019, all editions

Highlights

• Updates an issue with pasting mixed content of images and text from Microsoft Word into Internet Explorer. 
• Updates an issue that causes a text box that contains multiple lines of text to stop responding in certain scenarios. 
• Updates an issue that fails to print content that is outside of the margins of a document. 

Improvements and fixes

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

• Addresses an issue that occurs when a third-party application loads hidden tabs into Internet Options. 
• Addresses an issue with pasting mixed content of images and text from Microsoft Word into Internet Explorer. 
• Addresses an issue that causes a box that contains multiple lines of text to stop responding in certain scenarios. 
• Addresses an issue that prevents the first key stroke from being recognized correctly in the DataGridView cell. 
• Addresses an issue that causes an application that uses msctf.dll to stop working, and the 0xc0000005 (Access violation) exception appears. 
• Addresses an issue that prevents the correct lock screen from appearing when all of the following are true:
• The Group Policy Object (GPO) policy "Computer Configuration\Windows Settings\Security Settings\Local Policies\Security Options\Interactive Logon: Do not require Ctrl+Alt+Del Computer" is disabled.
• The GPO policy “Computer Configuration\Administrative Templates\System\Logon\Turn off app notifications on the lock screen” is enabled.
• The registry key HKLM\SOFTWARE\Policies\Microsoft\Windows\System\DisableLogonBackgroundImage is set to 1.
• Addresses a reliability issue in WDF01000.sys. 
• Addresses an issue that causes a KERNEL_SECURITY_CHECK_FAILURE (139) stop error when Windows resumes from Sleep and turns on certain Bluetooth headsets. 
• Addresses an issue that causes the Event Viewer Microsoft Management Console (MMC) to stop working when the secondary monitor is above the primary monitor. An out of bounds exception appears. 
• 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 prevents users from setting the REG_EXPAND_SZ keys in some automated scenarios. 
• 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 prevents hash signing using the Microsoft Platform Crypto Provider for TPMs from working correctly. This issue might also affect networking software, such as VPN applications. 
• 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 prevents a user’s PIN from being changed after connecting the device to Microsoft Workplace Join. 
• Addresses an issue that prevents applications running in an Azure Active Directory environment from receiving account change notifications. This occurs when using the Web Account Manager (WAM) and the WebAccountMonitor API. 
• Addresses an issue that fails to print content that is outside of the margins of a document. 
• 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 high CPU usage on Active Directory (AD) domain controllers when migrating to Windows Server 2019. This increases latency in Microsoft Exchange operations, causes Managed Store contention, and severely impacts index creation in Active Directory and the Global Catalog’s performance. 
• 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 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 might cause a deadlock in the Remote Desktop Gateway service. 
• Addresses an issue that might cause the Remote Desktop Gateway service to stop working. 
• Addresses an issue that causes systems to stop working with a 0x3B stop code when running a binary that is signed by a revoked certificate.
• Addresses an issue that prevents the Notification State registries from being deleted for certain apps even after the user profile is deleted.
• Addresses an issue that causes stop error 0x18 (REFERENCE_BY_POINTER) when Remote Desktop sessions redirect devices that are not input devices.
• Addresses an issue that displays a black screen to Windows Virtual Desktop users when they attempt to sign in.

April 21, 2020—KB4550969 (OS Build 17763.1192)

April 21, 2020—KB4550947 (OS Build 14393.3659)

Applies to: Windows 10, version 1607, all editions, Windows Server 2016

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.

April 21, 2020—KB4550947 (OS Build 14393.3659)

April 21, 2020—KB4550958 (Preview of Monthly Rollup)

Applies to: Windows 8.1, Windows Server 2012 R2, Windows Embedded 8.1 Industry Enterprise

Improvements and fixes

This non-security update includes improvements and fixes that were a part of KB4550961 (released April 14, 2020) and also includes these new quality improvements as a preview of the next Monthly Rollup update:

• 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 might cause certain operations, such as rename, to fail when you perform those operations on files or folders that are on a Cluster Shared Volume (CSV). The error is, “STATUS_BAD_IMPERSONATION_LEVEL (0xC00000A5)”. This issue occurs when you perform the operation on a CSV owner node from a process that doesn’t have administrator privilege.
• Addresses an issue that prevents certain apps from installing if they are published using a Group Policy Object.

April 21, 2020—KB4550958 (Preview of Monthly Rollup)