Download And Install KB4556799 Windows 10 Cumulative Update For May 2020 [Version 1909, 1903]

Microsoft’s cumulative security update, Patch Tuesday for May 2020, is available for download and installation. Since this is…

Installing KB4556799 in Windows 10

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:

List of critical security updates for Windows 10 May Update
List of critical security updates for Windows 10 May Update

You can also download the complete list of vulnerabilities from here:

Download And Install KB4556799 Windows 10 Cumulative Update For May 2020 [Version 1909, 1903] 1  List of security fixes for Windows 10 May Update (30.7 KiB, 1,046 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:

  1. Internet Explorer
  2. Microsoft Scripting Engine
  3. Windows App Platform and Frameworks
  4. Microsoft Graphics Component
  5. Windows Input and Composition
  6. Windows Media
  7. Windows Shell
  8. Microsoft Xbox
  9. Microsoft Edge
  10. Windows Fundamentals
  11. Windows Cryptography
  12. Windows Authentication
  13. Windows Kernel
  14. Windows Linux
  15. Windows Update Stack
  16. Windows Network Security and Containers
  17. Windows Active Directory
  18. Windows Storage and Filesystems
  19. Microsoft JET Database Engine

Install KB4556799 using Windows Update

If you have already installed the last cumulative update KB4550945 or KB4549951, only the new fixes will be installed while installing this update via 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)

KB4556799 available for download via Windows Update
KB4556799 available for download via Windows Update

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.

Download KB4556799 for Windows 10 Version 1909 64-bit [367.2 MB]

Download KB4556799 for Windows 10 Version 1903 64-bit [367.2 MB]

Download KB4556799 for Windows 10 Version 1909 32-bit [194.7 MB]

Download KB4556799 for Windows 10 Version 1903 32-bit [194.7 MB]

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.

Issues related to KB4556799

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

  1. Go to Windows Settings (Windows key + i) –> Update & Security –> Windows Update.
  2. From the right-hand pane, click on View Update History.
  3. Now click on Uninstall updates.
  4. 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:

  1. Open Command Prompt (Run –> cmd)
  2. Run the following command:
    wmic qfe list brief /format:table
  3. This will show all the updates installed on the computer. Make sure KB4556799 is on the list.
  4. 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
Windows image cleanup
Windows image cleanup

Also see:

Usman Khurshid is a seasoned IT Pro with over 15 years of experience in the IT industry. He has experience in everything from IT support, helpdesk, sysadmin, network admin, and cloud computing. He is also certified in Microsoft Technologies (MCTS and MCSA) and also Cisco Certified Professional in Routing and Switching.


  1. hi my name is king
    i want to send to me complete site for download windoes 10 version 2004

  2. Rajdeep Das says:


    1. I suspect the Windows File Explorer didn’t start after the restart process. Try pressing Ctrl + Shift + Esc. This will open the task manager. Go to File –> Start a new task. Enter “Explorer” without Quote and press Enter. This should open Windows Explorer and the Desktop will appear for you.

      Otherwise, you should look for windows Explorer process in the process list in Task Manager. Right-click it and select Restart.

  3. I have a problem about the usage of system process after I updated. The antimalware service executable and “System” just use all of my resource

  4. This update is causing problem s for me. I am on windows 1909 but after update, visual studio is unable to compile files. It is a big problem for me. VS simply gives error without any hint. When I try the uninstall options from windows update or command line, it gives a message
    “Update for Microsoft Windows (KB4556799) is required by your computer and cannot be uninstalled”. Did you guys try the uninstall at all?

    1. I was able to uninstall this update. Which command are you using to uninstall?
      Uninstalling KB4556799 Windows UPdate

  5. Many thanks for the article. As I have only just started to take an interest in the inner workings of Windows, so to speak, it was very informative. My only question is: if I run the clean up commands , do they clean up after all the previous updates, which I tend to do as I am told and simply install everything, or just the ones installed now.

    1. Yes the cleanup commands will cleanup all the space taken by Windows updates temporary files.
      I saved almost 4GB of space by running cleanup after the latest update.

      1. Peter Rielly says:

        Thanks. I`ll give it a go!

Comments are closed.