Introduction

In April 2025, Microsoft unveiled a groundbreaking feature for Windows 11 Enterprise users: Hotpatching. This innovation allows security updates to be applied without necessitating system reboots, marking a significant advancement in maintaining system security with minimal user disruption.

Background

Traditionally, applying security patches on Windows systems required a system restart to integrate updates fully. This process often led to downtime, affecting productivity and operational efficiency. Recognizing this challenge, Microsoft introduced Hotpatching, initially for Windows Server environments, and has now extended this capability to Windows 11 Enterprise clients.

How Hotpatching Works

Hotpatching operates by updating the in-memory code of running processes without restarting them. This method ensures that security patches take effect immediately upon installation, providing rapid protection against vulnerabilities. The process involves:

  • Baseline Updates: Released in the first month of each quarter (January, April, July, October), these updates include the latest security fixes, new features, and enhancements. They require a system restart.
  • Hotpatch Updates: Delivered in the subsequent two months of each quarter, these updates contain only security fixes and do not require a restart. This cycle reduces the number of required restarts from twelve to four annually.

Implementation and Requirements

To leverage Hotpatching, organizations need:

  • Windows 11 Enterprise, Version 24H2: Devices must run this version or later.
  • Microsoft Intune: For managing the deployment of Hotpatch updates.
  • Virtualization-Based Security (VBS): This feature must be enabled on devices.
  • Eligible Hardware: Devices with x64 (AMD/Intel) CPUs are supported. Arm64 devices are in public preview, requiring additional configuration.

Benefits

  • Immediate Protection: Security updates take effect immediately upon installation, reducing exposure to vulnerabilities.
  • Minimized Disruptions: Users can continue their work uninterrupted, as most security updates do not require a system restart.
  • Operational Efficiency: Reducing the frequency of required restarts enhances productivity and simplifies update management.

Implications and Impact

The introduction of Hotpatching signifies a shift in how organizations approach system security and maintenance. By minimizing downtime associated with updates, businesses can maintain higher levels of productivity and ensure continuous protection against emerging threats. This feature is particularly beneficial for environments where system availability is critical.

Technical Details

Hotpatching is managed through Windows Autopatch via the Microsoft Intune console. Administrators can create a Hotpatch-enabled quality update policy, and eligible devices will receive updates according to the defined schedule. It's important to note that while Hotpatch updates cover security fixes, other updates, such as feature enhancements and non-security fixes, are included in the baseline updates that require a restart.

Conclusion

Microsoft's introduction of Hotpatching for Windows 11 Enterprise represents a significant advancement in system maintenance and security. By enabling zero-reboot security updates, organizations can achieve a more seamless and efficient update process, enhancing both security posture and user experience.

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