ReFS volumes on removable media: enforcement phase: January 2027

January 2027In 53 daysMicrosoftEnforcementVendor gives the month only

ReFS volumes on removable media: enforcement phase

WindowsWindows Server

Who is affected: Devices that use ReFS on externally attached or removable storage. The October 2026 update started the audit phase; the January 2027 update can block affected volumes.
What to do: Review the audit events added by the October 2026 update to find external ReFS volumes.
Reformat or move data off unsupported external ReFS configurations before January 2027.
Source: Hardening changes for ReFS volumes on removable media“January 2027 Windows security update (Enforcement phase)”
Windows message center (Windows release health, Microsoft Learn)

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