Microsoft has released KB5083631, an optional cumulative update for Windows 11 that includes 34 changes. The update adds a new Xbox mode for Windows PCs, improves security and performance for batch files, and speeds up the launch of startup apps.
KB5083631 is a preview update, which means it lets administrators test bug fixes, improvements, and new features before they become broadly available in next month’s Patch Tuesday release. Unlike regular cumulative updates, monthly optional updates do not include security fixes and focus only on quality improvements.
In the April 2026 optional update, Microsoft improved the startup performance of apps listed under Settings > Apps > Startup, making them load faster when a device boots.
The update also introduces a new Xbox mode for Windows 11 PCs, including laptops, desktops, and tablets. This mode provides a full-screen gaming interface that keeps games in focus and reduces background distractions. Users can open Xbox mode from the Xbox app, Game Bar settings, or with the Windows logo key + F11 shortcut.
Another change in this preview update is improved security and performance for batch files and CMD scripts. This capability first appeared in February for Windows 11 Insiders in the Beta and Dev channels.
Microsoft said administrators can now enable a more secure processing mode for batch files. In this mode, batch files cannot be modified while they are running.
To install KB5083631, open Windows Settings, go to Windows Update, and select Check for Updates. Since this is an optional update, users must choose Download and install unless they prefer to install it manually from the Microsoft Update Catalog.
KB5083631 update highlights
After installation, this non-security update raises Windows 11 24H2 and 25H2 devices to builds 26100.8328 and 26200.8328, respectively.
The April 2026 preview update also includes several other notable changes:
- Supported input devices can now provide haptic feedback for certain actions, such as aligning objects in PowerPoint, snapping, or resizing windows. Haptic feedback can be managed in Settings > Bluetooth & devices > Mouse, Touchpad, or Pen > Haptic signals.
- [Secure Boot] Windows quality updates now include additional high-confidence device-targeting data, which expands the number of devices eligible to receive new Secure Boot certificates automatically. Devices get the new certificates only after enough successful update signals are collected, allowing for a controlled phased rollout.
- [Authentication (Kerberos)] The update improves Kerberos authentication for Remote Desktop sessions that use Remote Credential Guard, fixing error 0xc000009a.
- [Windows Security] Event logging related to CVE-2024-30098 now includes the name of the affected application. This makes it easier to identify apps that depend on smart card certificates and may need updates after recent security changes.
- The update removes a white flash that could appear when opening This PC or resizing the Details pane in dark mode.
- It also improves the reliability of explorer.exe so the process stops correctly after File Explorer windows are closed.
Microsoft also said updated Secure Boot certificates are now rolling out to replace the original 2011 certificates, which are set to expire in late June 2026. The company first outlined plans in January to refresh expiring Secure Boot certificates on eligible Windows 11 systems after warning administrators in November that the certificates needed to be updated before expiration.
Microsoft added that some Windows Server 2025 devices with an unrecommended BitLocker Group Policy configuration may boot into BitLocker recovery and require the recovery key on the first restart after KB5083631 is installed.
Earlier this month, Microsoft also released an out-of-band update to fix the March 2026 KB5079391 preview update, which was pulled after installation errors tied to 0x80073712.
