KB5021234 Cumulative updates for Windows 11 21H2

KB5021234 is a cumulative update for Windows 11 version 21H2. The update has been released as part of the ‘Patch Tuesday’ initiative of Microsoft on December 13, 2022. We look at some important points about KB5021234 below.

Salient points about KB5021234 for Windows 11

KB5021234 has now been superseded by January 2023’s cumulative update KB5022287 for Windows 11 21H2 edition. You may read more about KB5022287 on this page.

KB5021234 is the cumulative update for Windows 11 version 21H2. It corresponds to Windows 11 build 22000.1335. The update supersedes November month’s cumulative update KB5019961 for Windows 11.

Post-deployment of KB5019961, there was another out-of-band release of the preview update KB5019157 with Windows 11 build version 22000.1281.

Depending on the last deployment, if you installed KB5019961, you can skip KB5019157 and straight away install KB5021234 on Windows 11. This is because KB5021234 includes all the changes that are part of the KB5019157 preview update for Windows 11.

If you have already deployed KB5019157, you can proceed with the KB5021234 installation directly.

KB5021234 corresponds to the Servicing Stack Update 22000.1270. All the files of the Servicing Stack Update (SSU) are included in KB5021234. So, a separate installation of the Servicing Stack Update is not needed for KB5021234.

All the standard installation methods are available for installing KB5021234 on Windows 11 version 21H2 on x64 or ARM64 systems. You could use any of the following automated methods:

• Windows Update
• WSUS or Windows Server Update Service
• Windows Update for Business

Apart from this, you may also install KB5021234 manually through an offline installer file. The offline installer file is available as an MSU update file and can be downloaded from the Microsoft Update Catalog page for KB5021234.

The direct download links for KB5021234 for Windows 11 version 21H2 are shared below for ready reference:

• Download KB5021234 for Windows 11 x64 version – The size of this update file is 315.5 MB.
• Download KB5021234 for Windows 11 ARM64 version – The size of this update file is 432.6 MB.

Post-deployment issues on Windows 11 after installing KB5021234

After installing KB5021234, you may experience issues in connecting to the database through the Microsoft ODBC Sql driver. The summary of the issue is listed below:

After installing this update, apps that use ODBC connections through Microsoft ODBC SQL Server Driver (sqlsrv32.dll) to access databases might not connect. Additionally, you might receive an error in the app, or you might receive an error from the SQL Server. Errors you might receive include the following messages:

• The EMS System encountered a problem. Message: [Microsoft][ODBC SQL Server Driver] Protocol error in TDS Stream.
• The EMS System encountered a problem. Message: [Microsoft][ODBC SQL Server Driver] Unknown token received from SQL Server.

To decide whether you are using an affected app, open the app that connects to a database. Open a Command Prompt window, type the following command and then press Enter:

tasklist /m sqlsrv32.dll

If the command lists a task, then the app might be affected.

Microsoft is working on a fix for the database connectivity issues.

KB5021234 Changelog

The following issue fixes or improvements have been implemented in KB5021234 for Windows 11 version 21H2 for x64 and ARM64 systems:

• This update addresses an issue that affects remote networks. This issue stops you from reconnecting to them using DirectAccess.
• This update addresses an issue that might affect Data Protection Application Programming Interface (DPAPI) decryption. The decryption of a certificate private key might fail. Because of this, virtual private network (VPN) and other 802.1 certificate-based authentication might fail. This issue might occur when you encrypt the DPAPI master key with a wrong value.
• This update addresses a known issue that affects Direct Access. The issue might stop you from reconnecting to it after temporarily losing network connectivity. The issue might also occur when you switch between Wi-Fi networks or access points.