Microsoft Issues Alert: BitLocker Recovery Risk After October 2025 Updates

Microsoft has issued an urgent advisory for Windows users, confirming that a set of security updates released after 14 October 2025 may push some systems to the BitLocker recovery screen on restart. The issue, under active investigation, has led to reports of prompts for BitLocker recovery keys after device updates, primarily affecting recent Windows 11 client builds (25H2, 24H2) and Windows 10 (22H2).

According to Microsoft’s official incident postings (WI1183025, WI1183026, WI1183027), affected systems have required entering a BitLocker recovery key at startup, although normal operation resumes once the key is entered. The problem appears transient and closely tied to patch installations rather than persistent configuration or tampering, and is not believed to affect Windows Server versions at present.

Mitigations include a Known Issue Rollback (KIR); organisations are advised to contact Microsoft Support for guidance and to monitor the Windows Release Health dashboard, while ensuring BitLocker recovery information is retained and instructions for key retrieval are disseminated to staff.