Microsoft has released Windows Server vNext Insider Preview Build 29641 on August 10, 2026, which is the first preview based on the new Rubidium codebase. This build is available through the Experimental channel for Datacenter, Standard, and Azure configurations, but requires a clean install for users with earlier builds. Key features in this build include ReFS Boot, an NVMe over Fabrics initiator, Quick Machine Recovery, and Trusted Launch for Hyper-V VMs, though detailed release notes are not publicly accessible yet. Users are advised to install build 29531 or later to stay on the upgrade path, as upgrades from builds older than 29531 are not supported

Microsoft Releases Windows Server vNext Build 29641 on New Rubidium Codebase

Microsoft released Windows Server vNext Insider Preview Build 29641 to Insiders on August 10, 2026, marking the first preview based on the new internal Rubidium codebase. The build arrives via the Experimental channel as a testing-only LTSC Preview edition for Datacenter, Standard, and Azure configurations, though users must perform a clean install rather than upgrading from builds older than 29531. 29641 inherits major features like ReFS Boot, an NVMe over Fabrics initiator, Quick Machine Recovery, and Trusted Launch for Hyper-V VMs, though detailed release notes are currently gated behind authentication.

Microsoft Releases Windows Server vNext Build 29641 on New Rubidium Codebase @ NT Compatible