Microsoft has released the KB5083631 optional cumulative update for Windows 11, which includes 34 changes, such as a new Xbox mode for Windows PCs, enhanced security and performance for batch files, and performance improvements for launching startup apps.
KB5083631 is a preview update that lets admins test Windows bug fixes, improvements, and new features, before they’re generally available during next month’s Patch Tuesday release. However, unlike cumulative updates, monthly optional updates do not include security fixes and only roll out quality improvements.
With the April 2026 optional update, Microsoft has improved the performance of launching apps listed under Settings > Apps > Startup when the device starts.
It also added a new Xbox mode for Windows 11 PCs (e.g., laptops, desktops, and tablets), which provides a full‑screen interface that puts games front and center while minimizing background distractions. Users can enter Xbox mode from the Xbox app, Game Bar settings, or by using the Windows logo key + F11 keyboard shortcut.
Additionally, this month’s preview update introduces improved security and performance for batch files and CMD scripts, a change that first rolled out in February to Windows 11 Insiders in the Beta and Dev channels.
“Starting with this release, administrators can enable a more secure processing mode for batch files. This mode prevents batch files from changing during execution,” Microsoft explained.
You can install KB5083631 by opening Windows Settings, clicking on Windows Update, and then on ‘Check for Updates.’ However, since this is an optional update, you will need to click the ‘Download and install’ link if you don’t want to install it manually from the Microsoft Update Catalog.
KB5083631 update highlights
Once installed, this optional non-security update will update Windows 11 24H2 and 25H2 devices to builds 26100.8328 and 26200.8328, respectively.
The April 2026 preview update comes with dozens of other changes, some of the more important ones highlighted below:
- You can now experience haptic feedback on supported input devices when performing 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] With this update, Windows quality updates include additional high-confidence device-targeting data, increasing the coverage of devices eligible to receive new Secure Boot certificates automatically. Devices receive the new certificates only after demonstrating sufficient successful update signals, thereby maintaining a controlled, phased rollout. For more information, see Windows Secure Boot certificate expiration and CA updates.
- [Authentication (Kerberos)] This update improves Kerberos authentication for Remote Desktop sessions that use Remote Credential Guard, addressing error 0xc000009a.
- [Windows Security] This update improves event logging related to CVE‑2024‑30098 by including the name of the affected application. This change makes it easier to identify applications that rely on smart card certificates and may need updates following recent security changes.
- This update removes a white flash that could appear when opening This PC or while resizing the Details pane in dark mode.
- This update improves the reliability of relevant explorer.exe processes so they stop after File Explorer windows are closed.
Microsoft also noted that updated Secure Boot certificates are rolling out to replace the original 2011 certificates that will expire in late June 2026. In January, Microsoft first revealed plans to refresh expiring Secure Boot certificates on eligible Windows 11 systems, after warning admins in November to update the security certificates before they expire.
It also added that some Windows Server 2025 devices with “an unrecommended BitLocker Group Policy configuration” will boot into BitLocker recovery and require users to enter the BitLocker recovery key on the first restart after deploying the KB5083631 update.
Earlier this month, Microsoft also released an out-of-band update to fix the March 2026 KB5079391 preview update, which was pulled due to 0x80073712 errors during installation.
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