Microsoft releases out-of-band Windows 11 update to fix Office problems
Microsoft has been forced to release an unscheduled update for Windows 11. The newly unleashed KB5068221 update addresses issues with Microsoft Office running in virtualized environments.
For those who have been experiencing the issue, the fact that this update fixes things is reason enough to install it. But Microsoft has also used this update release to share details of a workaround for a SMBv1 share problem.
The KB5068221 update is a cumulative update, and it includes all of the security fixes and other improvements that were found in the KB5065426 update released earlier this month. In the release notes for the KB5068221update Microsoft describes the out-of-band update as including “quality improvements”.
Going into a little more detail, Microsoft explains the specific issue the update addresses:
[Virtualization and platform compatibility] Fixed: This update addresses an issue that affects Microsoft Office applications running in Microsoft Application Virtualization (App-V) environments. The failure occurred due to a double handle closure in the AppVEntSubsystems32 or AppVEntSubsystems64 system component.
The problems with Office are not the only ones introduced by September’s updates for Windows 11 – although it is the only one fixed by this out-of-band release. The updates from earlier in the month also caused issues with the Server Message Block (SMB) v1 protocol on NetBIOS over TCP/IP.
While this is a deprecated protocol, it remains in used by many and the impact of the interference was not insubstantial. Although a fix is yet to emerge, Microsoft has provided helpful advice in the release notes for the KB5068221 update.
The company describes the SMBv1 protocol connectivity issues, saying:
Symptoms
After installing this Windows update released on or after September 9, 2025, you might fail to connect to shared files and folders using the Server Message Block (SMB) v1 protocol on NetBIOS over TCP/IP (NetBT). This issue can occur if either the SMB client or the SMB server has the September 2025 security update installed.
Note: The SMBv1 protocol is deprecated and no longer installed by default in modern versions of Windows and Windows Server. Deployments that use newer versions of the protocol, SMBv2 or SMBv3, are not affected by this problem.
Microsoft then offers up the following by way of a workaround:
You can work around this issue by allowing network traffic on TCP port 445. By doing so, the Windows SMB connection will automatically switch to using TCP instead of NetBT, allowing the connection to resume successfully.
Although there is no date given, a fix is in the pipeline. Microsoft rolls out a standard statement about this, saying: “We are working on a resolution in a future Windows update and will provide more information when it is available”.
If you want – or need – to get hold of the KB5068221 update, you can download it from the Microsoft Update Catalog.
It is worth noting that the update contains one or more MSU files that require installation in a specific order. Microsoft provides the following instructions:
Method 1: Install all MSU files together
Download all MSU files for KB5068221 from Microsoft Update Catalog and place them in the same folder (for example, C:/Packages). Use Deployment Image Servicing and Management (DISM.exe) to install the target update. DISM will use the folder specified in PackagePath to discover and install one or more prerequisite MSU files as needed.
Updating Windows PC
To apply this update to a running Windows PC, run the following command from an elevated Command Prompt:
DISM /Online /Add-Package /PackagePath:c:\packages\Windows11.0-KB5068221-x64.msu Or, run the following command from an elevated Windows PowerShell prompt:
Add-WindowsPackage -Online -PackagePath "c:\packages\Windows11.0-KB5068221-x64.msu" Updating Windows Installation media
To apply this update to Windows Installation media, see Update Windows installation media with Dynamic Update.
Note: When downloading other Dynamic Update packages, ensure they match the same month as this KB. If the SafeOS Dynamic Update or Setup Dynamic Update is not available for the same month as this KB, use the most recently published version of each.
To add this update to a mounted image, run the following command from an elevated Command Prompt:
DISM /Image:mountdir /Add-Package /PackagePath:Windows11.0-KB5068221-x64.msu Or, run the following command from an elevated Windows PowerShell prompt:
Add-WindowsPackage -Path "c:\offline" -PackagePath "Windows11.0-KB5068221-x64.msu" -PreventPending Method 2: Install each MSU file individually in order
Download and install each MSU file individually using DISM or Windows Update Standalone Installer in the following order:
- windows11.0-kb5043080-x64_953449672073f8fb99badb4cc6d5d7849b9c83e8.msu
- windows11.0-kb5068221-x64_6640d1a7a2a393bd2db6f97b7eb4fe3907806902.msu