In the Fall Creators Update, Microsoft is removing the ability to create volumes using its new ReFS file system from Windows 10 Pro. Existing volumes will continue to work, but Pro will no longer be able to create new ones.

After rumors in June, Microsoft confirmed last week that it was producing yet another variant of Windows 10: Pro for Workstations. The main features of this build are that it lifts certain limits found in regular Pro: up to four processors (compared to two in Pro) and 6TB of RAM (compared to 2TB). It also has support for certain exotic server-grade hardware, including non-volatile main memory and high-speed network adaptors.

Microsoft is promoting one final feature in Pro for Workstations: its new, modern file system, ReFS ("resilient file system"). ReFS—like modern file systems on other platforms such as Oracle's ZFS and Linux's btrfs—includes integrated checksums to detect data corruption. Combined with Storage Spaces, it can automatically reconstruct damaged data from software-defined arrays.

Promoting this as a feature of Pro for Workstations was, however, a little odd; current Windows 10 Pro already supports ReFS and can be used to create ReFS volumes on Storage Spaces. Windows machines must still use the traditional NTFS file system for certain roles, as ReFS isn't yet bootable—something that remains true even in Pro for Workstations. But the file system itself works and is supported.

However, Twitter user Tero Alhonen spotted that the list of features removed or deprecated in the Fall Creators Update now includes the creation of ReFS volumes in Windows 10 Pro. Windows 10 Enterprise (available only to volume license customers) and Windows 10 Pro for Workstations will be the only versions of Windows 10 to retain the ability to create ReFS volumes.

While ReFS is not a mainstream feature—it's optimized for large volumes and particularly for workloads such as storing virtual machine system images—this nonetheless feels like a strange move in the wrong direction. NTFS is a robust, well-tested file system, and it is certainly the better mainstream choice today. But its functional shortcomings are becoming more stark, especially when compared to cutting-edge file systems on other platforms. Linux users have a wide range of flexible software RAID capabilities integrated with modern file systems. Even macOS is starting to show up Windows in this area with its new APFS file system and Fusion Drive hybrid storage capability.

Microsoft has been developing some broadly comparable capabilities with ReFS, Storage Spaces, and Storage Spaces Direct. But these features have been substantially restricted to server versions of Windows. With this move, the new abilities are retreating even further into the high-end (and high-priced) market and becoming even less widely useful as a result. This feels like the opposite direction that such features should be moving in.