- June 2021 Security Updates release notes
- List of software updates for Microsoft products
- List of the latest Windows Updates and Services Packs
- Security Updates Guide
- Microsoft Update Catalog site
- Our in-depth Windows update guide
- How to install optional updates on Windows 10
- Windows 10 Update History
- Windows 8.1 Update History
- Windows 7 Update History
Microsoft Windows Security Updates June 2021 overview

Microsoft released security updates and non-security updates for all supported client and server versions of Microsoft's Windows operating system as well as other company products. The June 2021 Patch Day is the first that includes Windows 10 version 21H1, the latest Windows 10 feature update that Microsoft released last month.
Our overview links to the security updates that Microsoft released, to support articles and downloads, lists known issues as revealed by Microsoft, and provides system administrators and home users with other relevant information.
Check out the May 2021 Patch overview here in case you want to revisit it.
The Microsoft Windows Security Updates: June 2021
You may download the following Excel spreadsheet to get a list of the security updates released for Microsoft Windows and other company products: Security Updates 2021-06-08-070201pm
Executive Summary
- Windows 10 version 21H1 was released last month. It is rolled out gradually to systems running Windows 10 version 2004 and 20H2 currently.
- All client and server versions of Windows are affected by at least 1 critical security vulnerability.
- Microsoft released updates for other products including Microsoft Office, Microsoft Intune, 3D Viewer, .Net Core & Visual Studio, Windows Defender, Paint 3D and Windows Installer.
Operating System Distribution
- Windows 7 (extended support only): 14 vulnerabilities: 2 critical and 12 important
- Windows MSHTML Platform Remote Code Execution Vulnerability - CVE-2021-33742
- Scripting Engine Memory Corruption Vulnerability -- CVE-2021-31959
- Windows 8.1: 19 vulnerabilities: 2 critical and 12 important
- same critical as Windows 7
- Windows 10 version 1903 and 1909: 24 vulnerabilities: 2 critical and 22 important
- same critical as Windows 7
- Windows 10 version 2004, 20H2 and 21H1 : 25 vulnerabilities, 2 critical and 23 important
- same critical as Windows 7
Windows Server products
- Windows Server 2008 R2 (extended support only): 12 vulnerabilities: 1 critical and 11 important
- Windows MSHTML Platform Remote Code Execution Vulnerability -- CVE-2021-33742
- Windows Server 2012 R2: 19 vulnerabilities: 2 critical and 17 important
- Scripting Engine Memory Corruption Vulnerability -- CVE-2021-31959
- Windows MSHTML Platform Remote Code Execution Vulnerability -- CVE-2021-33742
- Windows Server 2016: 20 vulnerabilities: 2 critical and 18 important.
- same as Windows Server 2012 R2
- Windows Server 2019: 24 vulnerabilities: 2 critical and 22 important
- same as Windows Server 2012 R2
Windows Security Updates
Windows 7 SP1 and Windows Server 2008 R2
Updates and improvements:
- Security updates
- Fixes an issue in the SMB (Server Message Block) protocol which caused frequent crashes with stop error code 0xA on Windows Server 2008 R2 SP1 devices. (Security-only)
Windows 8.1 and Windows Server 2012 R2
Updates and improvements:
- Security updates
Windows 10 version 1909
- Support Page: KB5003635
Updates and improvements:
- Addresses an issue with an inconsistent shutdown during Windows Update that damages the Windows Management Instrumentation (WMI) repository.
- Addresses an issue that might prevent you from signing in to some Microsoft 365 desktop client apps after installing the May 11, 2021 or later update and restarting your device
- Security updates
Windows 10 version 2004, 20H2 and 21H1
- Support Page: KB5003637
Updates and improvements:
- Security updates
Other security updates
2021-06 Cumulative Security Update for Internet Explorer (KB5003636)
2021-06 Security Monthly Quality Rollup for Windows Server 2008 (KB5003661)
2021-06 Security Only Quality Update for Windows Server 2008 (KB5003695)
2021-06 Security Only Quality Update for Windows Embedded 8 Standard and Windows Server 2012 (KB5003696)
2021-06 Security Monthly Quality Rollup for Windows Embedded 8 Standard and Windows Server 2012 (KB5003697)
2021-06 Security Only Quality Update for Windows 8.1 and Windows Server 2012 R2 (KB5003681)
Known Issues
Windows 7 SP1 and Server 2008 R2
- Connections to SQL Server 2005 may fail after installation of the update. Error "Cannot connect to <Server name>" may be displayed.
- Microsoft notes that the behavior is expected and suggests that customers upgrade to a supported version of SQL server.
- Installed update may be reverted.
- Expected behavior if the machine is not supported for ESU.
- Certain operations may fail on Cluster Shared Volumes.
- Either perform the operation from a process with administrator privileges, or from a node that does not have CSV ownership.
Windows 8.1 and Server 2012 R2
- Certain operations may fail on Cluster Shared Volumes.
- Either perform the operation from a process with administrator privileges, or from a node that does not have CSV ownership.
Windows 10 version 1909
- System and user certificates may be lost when the device is updated to a newer version of Windows 10.
- Microsoft suggests to go back to the previous version of Windows, but it is only available up to 30 days after installation of the update.
Windows 10 version 2004, 20H2 and 21H1
- Same system and user certificates issue as version 1909.
- Issue with the Microsoft Japanese Input Method Editor and Japanese Kanji / Furigana characters.
- No workaround at the time of writing. Microsoft is working on a resolution.
- Issues with the performance of games after installing recent updates.
- Is resolved according to Microsoft except for Enterprise-managed devices.
- Issue with Microsoft Edge Legacy being removed but Microsoft Edge (new) not being installed if W10 is installed using custom offline media or ISO images.
- Workaround provided on the support page.
Security advisories and updates
ADV 990001 -- Latest Servicing Stack Updates
Other updates
2021-06 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows Server, version 20H2, Windows 10 Version 20H2, Windows Server, version 2004, Windows 10 Version 2004, Windows 10 Version 1909, and Windows 10 Version 1903 (KB5003254)
2021-06 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 1909 (KB5003256)
2021-06 Cumulative Update for .NET Framework 3.5 and 4.8 for Microsoft server operating system for ARM64 (KB5003529)
2021-06 Cumulative Update for .NET Framework 4.8 for Windows Server 2016 and Windows 10 Version 1607 (KB5003542)
2021-06 Cumulative Update for Windows 10 Version 1607 (KB5003638)
2021-06 Cumulative Update for Microsoft server operating system version 21H2 for ARM64-basedSystems (KB5003645)
2021-06 Servicing Stack Update for Windows 10 Version 1909 (KB5003710)
2021-06 Servicing Stack Update for Windows Server 2019 and Windows 10 Version 1809 (KB5003711)
2021-06 Cumulative Update for .NET Framework 3.5, 4.7.2 and 4.8 for Windows Server 2019 and Windows 10 Version 1809 (KB5003778)
2021-06 Cumulative Update for .NET Framework 3.5 and 4.8 for Windows 10 Version 20H2, Windows 10 Version 2004, Windows 10 Version 1909, and Windows 10 Version 1903 (KB5004034)
2021-06 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB5003543)
2021-06 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded 8 Standard and Windows Server 2012 (KB5003544)
2021-06 Security and Quality Rollup for .NET Framework 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB5003545)
2021-06 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB5003547)
2021-06 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded 8 Standard and Windows Server 2012 (KB5003548)
2021-06 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows 8.1 and Windows Server 2012 R2 (KB5003549)
2021-06 Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB5003779)
2021-06 Security and Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded 8 Standard and Windows Server 2012 (KB5003780)
2021-06 Security and Quality Rollup for .NET Framework 3.5, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows 8.1 and Windows Server 2012 R2 (KB5003781)
2021-06 Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 and 4.6.2 for Windows Server 2008 (KB5003782)
2020-05 Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4552951)
2020-05 Security Only Update for .NET Framework 4.5.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4552952)
2020-05 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4552953)
2020-05 Security Only Update for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4556403)
2020-05 Security Only Update for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4556406)
2020-07 Security Only Update for .NET Framework 4.5.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4565583)
2020-07 Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4565586)
2020-07 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4565589)
2020-07 Security Only Update for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4566466)
2020-07 Security Only Update for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4566469)
2020-08 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4569733)
2020-08 Security Only Update for .NET Framework 4.6 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4569740)
2020-08 Security Only Update for .NET Framework 4.5.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4569743)
2020-08 Security Only Update for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4570500)
2020-08 Security Only Update for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4570503)
2020-09 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4576490)
2020-10 Security and Quality Rollup for .NET Framework 4.5.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4578955)
2020-10 Security and Quality Rollup for .NET Framework 4.6 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4578963)
2020-10 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4578977)
2020-10 Security Only Update for .NET Framework 4.5.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4578983)
2020-10 Security Only Update for .NET Framework 4.6 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4578987)
2020-10 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4578990)
2020-10 Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4579977)
2020-10 Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4579980)
2020-10 Security Only Update for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4580467)
2020-10 Security Only Update for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4580470)
2021-02 Security and Quality Rollup for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4600944)
2021-02 Security and Quality Rollup for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4600945)
2021-02 Security Only Update for .NET Framework 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4601089)
2021-02 Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2 for Windows Embedded Standard 7, Windows 7, Windows Server 2008 R2, and Windows Server 2008 (KB4601090)
2021-02 Security Only Update for .NET Framework 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4602958)
2021-02 Security Only Update for .NET Framework 4.6 for Windows Server 2008 (KB4602961)
2021-02 Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB4603002)
2021-02 Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB4603005)
2021-05 Security and Quality Rollup for .NET Framework 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8 for Windows Embedded Standard 7, Windows 7, and Windows Server 2008 R2 (KB5001878)
2021-05 Security and Quality Rollup for .NET Framework 2.0, 3.0, 4.5.2, 4.6 for Windows Server 2008 (KB5001882)
Microsoft Office Updates
You find Office update information here.
How to download and install the June 2021 security updates
Security updates are downloaded and installed automatically on most Home systems running Windows. The updates are also released via WSUS and other update management systems, and provided as direct downloads on Microsoft's Update Catalog website.
You can check for updates in the following way on Windows when using Windows Updates:
- Select Start, type Windows Update and load the Windows Update item that is displayed.
- Select check for updates to run a manual check for updates.
Direct update downloads
Below are resource pages with direct download links, if you prefer to download the updates to install them manually.
Windows 7 and Server 2008 R2
- KB5003667 -- 2021-06 Security Monthly Quality Rollup for Windows 7
- KB5003694 -- 2021-06 Security Only Quality Update for Windows 7
Windows 8.1 and Windows Server 2012 R2
- KB5003671 -- 2021-06 Security Monthly Quality Rollup for Windows 8.1
- KB5003681 -- 2021-06 Security Only Quality Update for Windows 8.1
Windows 10 (version 1909)
- KB5003635 -- 2021-06 Cumulative Update for Windows 10 Version 1909
Windows 10 (version 2004)
- KB5003637 -- 2021-06 Cumulative Update for Windows 10 Version 2004
Windows 10 (version 20H2)
- KB5003637 -- 2021-06 Cumulative Update for Windows 10 Version 20H2
Windows 10 (version 21H1)
- KB5003637 -- 2021-06 Cumulative Update for Windows 10 Version 21H1
Additional resources


What mental age of reader are you targeting with the first sentence? 10?
Why not write an article on how to *avoid* upgrading from W10 to W11. Analogous to those like me who avoided upgrading from 7 to 10 for as long as possible.
If your paymaster Microsoft permits it, of course.
5. Rufus
6. Ventoy
PS. I hate reading these “SEO optimized” articles.
I used Rufus to create an installer for a 6th gen intel i5 that had MBR. It upgraded using Setup. No issues except for Win 11 always prompting me to replace my local account. Still using Win 10 Pro on all my other PCs to avoid the bullying.
bit pointless to upgrade for the sake of upgrading as you never know when you’ll get locked out because ms might suddenly not provide updates to unsupported systems.
ps…. time travelling?
written. Jan 15, 2023
Updated • Jan 13, 2023
This happens when you schedule a post in WordPress and update it before setting the publication date.
Anyone willing to downgrade to this awful OS must like inflicting themselves with harm.
I have become convinced now that anybody who has no qualms with using Windows 11/10 must fit into one of the following brackets:
1) Too young to remember a time before W10 and W11 (doesn’t know better)
2) Wants to play the latest games on their PC above anything else (or deeply needs some software which already dropped W7 support)
3) Doesn’t know too much about how computers work, worried that they’d be absolutely lost and in trouble without the “”latest security””
4) Microsoft apologist that tries to justify that the latest “features” and “changes” are actually a good thing, that improve Windows
5) Uses their computer to do a bare minimum of like 3 different things, browse web, check emails, etc, so really doesn’t fuss
Obviously that doesn’t cover everyone, there’s also the category that:
6) Actually liked W7 more than 10, and held out as long as possible before switching, begrudgingly uses 10 now
Have I missed any group off this list?
You have missed in this group just about any professional user that uses business software like CAD programs or ERP Programs which are 99% of all professional users from this list.
Linux doesn’t help anyone who is not a linux kid and apple is just a fancy facebook machine.
Microsoft has removed KB5029351 update
only from windows update though
KB5029351 is still available from the ms update catalog site
1. This update is labaled as PREVIEW if it causes issues to unintelligent people, then they shouldn’t have allowed Preview updates ot install.
2. I have installed it in a 11 years old computer, and no problems at all.
3. Making a big drama over a bluescreen for an updated labeled as preview is ridiculous.
This is probably another BS internet drama where people ran programs and scripts that modified the registry until they broke Windows, just for removing stuff that they weren’t even using just for the sake of it.
Maybe people should stop playing geeks and actually either use Windows 10 or Windows 11, but don’t try to modify things just for the sake of it.
Sometimes removing or stopping things (like defender is a perfect example) only need intelligence, not scripts or 3rd party programs that might mess with windows.
Windows 11 was a pointless release, it was just created because some of the Windows team wanted to boost sales with some sort of new and improved Windows 10. Instead, Microsoft cannot support one version well let alone two.
Windows 11 is the worst ugly shame by Microsoft ever. They should release with every new W11 version a complete free version of Starallback inside just to make this sh** OS functionally again.
motherboard maker MSI has recently released a statement regarding the “unsupported processor” blue screen error for their boards using Intel 600/700 series chipsets & to avoid the KB5029351 Win11 update:
https://www.msi.com/news/detail/MSI-On–UNSUPPORTED-PROCESSOR–Error-Message-of-Windows-11-Update-KB5029351-Preview-142215
check out the following recent articles:
Neowin – Microsoft puts little blame on its Windows update after UNSUPPORTED PROCESSOR BSOD bug:
https://www.neowin.net/news/microsoft-puts-little-blame-on-its-windows-update-after-unsupported-processor-bsod-bug/
BleepingComputer – Microsoft blames ‘unsupported processor’ blue screens on OEM vendors:
https://www.bleepingcomputer.com/news/microsoft/microsoft-blames-unsupported-processor-blue-screens-on-oem-vendors/
While there may be changes or updates to the Windows 10 Store for Business and Education in the future, it is premature to conclude that it will be discontinued based solely on rumors.
My advice, I left win 15 years ago. Now I’m a happy linux user (linuxmint) but there is Centos, Fedora, Ubuntu depending on your needs.
motherboard maker MSI has recently released new BIOS/firmware updates for their Intel 600 & 700 series motherboards to fix the “UNSUPPORTED_PROCESSOR” problem (Sept. 6):
https://www.msi.com/news/detail/Updated-BIOS-fixes-Error-Message–UNSUPPORTED-PROCESSOR–caused-BSOD-on-MSI-s-Intel-700-and-600-Series-Motherboards-142277
I try to disable the Diagnostics Tracking Service (Connected Devices Platform User Services) but it wont let me disable it, any help will be greatly appreciated.
Tank you for your help