Windows Server Insider Preview Build 16267. There are no new features in build 16267, but some known issues and General Scenario Highlights. Microsoft recommends a clean install for the best experience with this preview build. The latest Windows Server build and matching symbols are available for download here.

NOTE:The expiration date for this server preview build is 12/4/2017.

The following keys are available for unlimited activations of Windows Server. These keys may be used throughout the pre-release cycle.

  • Windows Server Datacenter Core: B69WH-PRNHK-BXVK3-P9XF7-XD84W
  • Windows Server Standard Core: V6N4W-86M3X-J77X3-JF6XW-D9PRV

General Scenario Highlights

Developers and Containers:

  • New base container images (available on Windows Insider Docker Hub repo)
  • Optimized Nano Server base image (over 70% smaller)
  • The PowerShell team is providing a preview image based on PowerShell 6.0
  • The .NET team is providing a preview image based on Nano Server with .NET Core 2.0
  • Optimized Server Core base image (over 20% smaller)
  • Support for SMB volume mounting
  • Infrastructure for Orchestrators
  • Networking enhancements for ongoing Kubernetes work
  • Named pipe mapping support
  • Bug fixes, performance enhancements

Cloud Guest:

  • TLS info: administrators can make specific recommendations to default to HTTPS
  • Storage Replica Test Failover
  • vPMEM in Guest: Tenants can use and manage PMEM/SCM
  • Tenant-Aware VM Start Ordering: App Ready / OS Heartbeat for better load balancing
  • Guest RDMA
  • Improvement in time accuracy
  • Azure enlightened clusters – optimized to run on Azure IaaS

Cloud Host:

  • Software Defined Data Center (SDDC) host
  • Shielded Linux VM
  • SDN: Encrypted virtual networks
  • Secure clusters
  • SMB 1 disabled by default
  • SDN: Reduced downtime for tenant connections through gateways
  • Spaces Direct: Scoped Spaces to mitigate impact of multi-node loss
  • Spaces Direct: Marginal drive handling for predictive detection of drive failure
  • Data Deduplication available for ReFS
  • New Data Deduplication DataPort API for optimized ingress/egress
  • Space efficiency with ReFS Compaction
  • Performant Spaces Direct Multi Resilient Volumes (MRV)
  • Cluster Sets: Significantly increases hyper-converged SDDC cloud scale by grouping multiple clusters into a larger fabric
  • Support for Storage Class Memory (SCM) in Spaces Direct

Known issues 

  • Cluster Sets: A couple of key functionalities to enable end-to-end testing of Cluster Sets scenarios are not present in this build, so defer all evaluation of this scenario to a future build.
  • When a computer runs the Windows Preinstallation Environment (WinPE) from a local drive, the EFI system partition, which contains the WinPE image (boot.wim), does not have a drive letter assigned. This issue can adversely affect some automation.
  • Apps that call into the firewall, such apps that use networking, may become unresponsive until the user reboots because of an application hang end-task error (0xCFFFFFFF) in the Windows firewall API library (FirewallAPI.dll), which occurs when the library is blocked on an advanced local procedure call (ALPC) port while attempting to diagnose a connection failure and retrieve information.
  • A stop error may occur during volume repair in a cluster. The recommended workaround is to restart the computer. No corruption or data loss is expected.

Be sure to use the Feedback Hub and submit your feedback to Microsoft once you’ve downloaded this build, as it will prove very valuable to the development process.