March 12, 2020—KB4551762 (OS Builds 18362.720 and 18363.720)

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

Highlights


  • Updates a Microsoft Server Message Block 3.1.1 protocol issue that provides shared access to files and printers.

Improvements and fixes


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


Symptom Workaround
When using Windows Server containers with the March 10, 2020 updates, you might encounter issues with 32-bit applications and processes. For important guidance on updating Windows containers, please see Windows container version compatibility and Update Windows Server containers.
Devices using a manual or auto-configured proxy, especially with a virtual private network (VPN), might show limited or no internet connection status in the Network Connectivity Status Indicator (NCSI) in the notification area. This might happen when connected to or disconnected from a VPN or after changing the state between the two. Devices with this issue might also have issues reaching the internet using applications that use WinHTTP or WinInet. Examples of apps that might be affected on devices in this state include, but are not limited to, Microsoft Teams, Microsoft Office, Microsoft Office 365, Microsoft Outlook, Internet Explorer 11, and some versions of Microsoft Edge. This issue is resolved in KB4554364.

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 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 (KB4541338) 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 and Microsoft Update Yes None. This update will be downloaded and installed automatically from Windows Update.
Microsoft Update Catalog Yes To get the standalone package for this update, go to the Microsoft Update Catalog website.
Windows Server Update Services (WSUS) Yes

This update will automatically sync with WSUS if you configure Products and Classifications as follows:

Product: Windows 10, version 1903 and later

Classification: Security Updates

 

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4551762

Note Some files erroneously have “Not applicable” in the “File version” column of the CSV file. This might lead to false positives or false negatives when using some third-party scan detection tools to validate the build.