Windows 11 24H2 Update KB5068221 Resolves Issues with Office Applications

Microsoft has issued an out-of-band update targeting Windows 11 version 24H2 to rectify issues encountered within Microsoft Office applications across specific environments. The update, identified as KB5068221, comes with the build number 26100.6588 and contains a singular fix, a common trait of unscheduled updates.

[Virtualization and platform compatibility] Fixed: This update resolves a critical problem affecting Microsoft Office applications that operate in Microsoft Application Virtualization (App-V) environments. The issue stemmed from a double handle closure within the AppVEntSubsystems32 or AppVEntSubsystems64 system components.

This update also brings to light a known issue that has been traced back to earlier versions, notably this month’s security update labeled KB5065426, which also experiences complications in DRM/HDCP playback. Users may face challenges when attempting to connect to shared files and folders utilizing the SMB v1 protocol:

Symptoms	Workaround
Post-installation of this Windows update—as of or after September 9, 2025—you may encounter connectivity issues with shared files and folders using the Server Message Block (SMB) v1 protocol over NetBIOS via TCP/IP (NetBT).This connectivity failure could arise if either the SMB client or server includes the September 2025 security update. Note: The SMBv1 protocol is heavily deprecated and is not installed by default in contemporary Windows and Windows Server versions. Systems utilizing newer protocols, such as SMBv2 or SMBv3, are not impacted by this issue.	A viable workaround includes enabling network traffic on TCP port 445. This adjustment will prompt the Windows SMB connection to default to TCP, thereby restoring connectivity. Efforts are underway to devise a resolution in a forthcoming Windows update, with further details to be shared when available.

Symptoms

Workaround

Post-installation of this Windows update—as of or after September 9, 2025—you may encounter connectivity issues with shared files and folders using the Server Message Block (SMB) v1 protocol over NetBIOS via TCP/IP (NetBT).This connectivity failure could arise if either the SMB client or server includes the September 2025 security update.

Note: The SMBv1 protocol is heavily deprecated and is not installed by default in contemporary Windows and Windows Server versions. Systems utilizing newer protocols, such as SMBv2 or SMBv3, are not impacted by this issue.

A viable workaround includes enabling network traffic on TCP port 445. This adjustment will prompt the Windows SMB connection to default to TCP, thereby restoring connectivity.

Efforts are underway to devise a resolution in a forthcoming Windows update, with further details to be shared when available.

To download KB5068221, navigate to Settings > Windows Update. Alternatively, you can access it through the Microsoft Update Catalog by clicking here. Additionally, Microsoft has issued a reminder regarding the expiration of original Secure Boot certificates, urging users to prepare for an upgrade. For more information on this matter, please refer to the relevant article.

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