Microsoft’s cumulative security update, Patch Tuesday for May 2020, is available for download and installation. Since this is a mandatory update, if you have turned on Windows Updates, KB4556799 will be installed automatically on your Windows 10 Version 1903/1909 system.
After KB4556799 is installed, Windows 10 Version 1903 build no. will be 18362.836 and Windows 10 Version 1909 build no. will be 18363.836.
Due to the public health situation all over the world, from May 2020 onward, Microsoft has decided that there will be no optional non-security related updates. That means we will possibly get only one cumulative update per month and that will be on Patch Tuesday. The C and D cumulative updates have been paused.
What’s new in KB4556799
According to Microsoft Security Response Center, a total of 464 vulnerabilities have been fixed in all Windows 10 Version 1903/1909 versions, including 32-bit, 64-bit and ARM64 based systems.
Of these, 30 are critical and 434 are important. Here is a screenshot of the critical vulnerabilities:
You can also download the complete list of vulnerabilities from here:
List of security fixes for Windows 10 May Update (30.7 KiB, 1,197 hits)
Some highlights of this cumulative update include:
- Updates to improve security when using Internet Explorer and Microsoft Edge.
- Updates to improve security when using input devices such as a mouse, keyboard, or stylus.
- Updates to verify usernames and passwords.
- Updates to improve security when using Microsoft Xbox.
- Updates to improve security when Windows performs basic operations.
- Updates for storing and managing files.
- Updates to improve security when using Microsoft Office products.
Basically, this update will improve the security of the following Windows components:
- Internet Explorer
- Microsoft Scripting Engine
- Windows App Platform and Frameworks
- Microsoft Graphics Component
- Windows Input and Composition
- Windows Media
- Windows Shell
- Microsoft Xbox
- Microsoft Edge
- Windows Fundamentals
- Windows Cryptography
- Windows Authentication
- Windows Kernel
- Windows Linux
- Windows Update Stack
- Windows Network Security and Containers
- Windows Active Directory
- Windows Storage and Filesystems
- Microsoft JET Database Engine
Install KB4556799 using Windows Update
It took me around 10 to 12 minutes to install the update including restarting my system.
If you are missing any previous updates, installing KB4556799 will install all the security fixes included in all previous updates.
To install this update using Windows Update, please go to Windows Settings –> Update & Security –> Windows Update. In the right-hand pane, click on the Check for updates button.
You will see the following updates are available:
2020-05 Cumulative Update for Windows 10 Version 1909 for x64-based Systems (KB4556799)
Since this is a mandatory update, it will download and install automatically. Once installed, you will need to restart the system for the changes to take effect.
Download KB4556799 Offline installers
You can also download this cumulative update and then install it on any system without requiring any Internet connection.
To install the update, simply run the downloaded MSU file and Windows will automatically install the cumulative update.
You can check your current Windows build by going to Run –> winver.
Although it has been a few hours since this update was released, I have been following a lot of forums including tenforums, Microsoft Answers, Reddit etc. but have not read any issues from people who have already installed this update.
I’ll update this section if I encounter any issue regarding KB4556799. If you come across any issue, please share it in the comments below.
Uninstall KB4556799 cumulative update
At the time of this writing, I did not find any problem being discussed in different forums regarding this update.
However, if you are having issues with this update, it can be uninstalled in two ways:
Uninstall KB4556799 using Windows Update History tool
- Go to Windows Settings (Windows key + i) –> Update & Security –> Windows Update.
- From the right-hand pane, click on View Update History.
- Now click on Uninstall updates.
- Select Update for Microsoft Windows (KB4556799) and press the Uninstall button.
Uninstall KB4556799 using command-line
Another quick way to uninstall this update is by using the command prompt. Here are the commands:
- Open Command Prompt (Run –> cmd)
- Run the following command:
wmic qfe list brief /format:table
- This will show all the updates installed on the computer. Make sure KB4556799 is on the list.
- To uninstall the update, run the following command
wusa /uninstall /kb:4556799
The system needs to be restarted after uninstalling the update.
Cleanup after installing Windows Updates
If you want to save space after installing Windows updates, you can run the following commands:
dism.exe /Online /Cleanup-Image /AnalyzeComponentStore
dism.exe /Online /Cleanup-Image /StartComponentCleanup