Microsoft Issues Warning on BitLocker Recovery for Windows Updates

Microsoft has identified a significant issue affecting users of Windows 11, particularly those running versions 25H2 and 24H2, as well as Windows 10. The problem arises from the October 2025 update, which may unexpectedly trigger BitLocker Recovery, requiring users to input their BitLocker recovery key. If users do not possess this key, they risk losing access to their data. Fortunately, the recovery key is typically synced with the user's Microsoft account, providing a potential safeguard against data loss.

BitLocker is a disk encryption feature designed to protect data by preventing unauthorised access. However, users unfamiliar with its functioning may find themselves in a precarious situation if they are prompted for a recovery key without having prepared for such an event.

In a recent support document, Microsoft confirmed, "After installing Windows Updates released on or after October 14, 2025, some devices might encounter issues during restart or startup." This advisory is currently accessible only to users with Microsoft 365 Business or Windows 11 Enterprise licenses.

The versions of Windows that are reported to be affected include Windows 11 25H2, Windows 11 24H2, and certain builds of Windows 10. Microsoft is in the process of rolling out a fix, but business users will need to implement this manually across their organisations.

The company noted that the BitLocker recovery prompts are predominantly observed on Intel-based systems equipped with a feature known as "Connected Standby." Connected Standby, also referred to as Modern Standby, enables devices to maintain network connectivity while in a low-power state. This feature has been present since the introduction of Windows 8 and has evolved with subsequent updates.

Although Microsoft has not disclosed the precise relationship between the BitLocker issues and the Connected Standby feature, it is speculated that the October 2025 update may have disrupted the boot chain or Secure Boot state. In cases involving Intel machines, it appears that the update or restart process did not properly suspend BitLocker for a single reboot, leading to the recovery prompt.

Reports from users experiencing these issues have surfaced on various forums, including the Feedback Hub. One administrator highlighted that three of their devices encountered BitLocker recovery prompts after the installation of Windows 11 update KB5066835. While entering the recovery key allowed the devices to boot, one unit continued to request the key daily.

A user on Reddit mentioned, "We have three Windows 11 24H2 Azure virtual machines that cannot boot anymore after the update. They are stuck in BitLocker recovery." Another user noted issues specifically with HP Pro Mini 400 G9 desktops, which have also faced challenges during enrollment into Microsoft Intune due to TPM errors.

For users uncertain about whether BitLocker is enabled on their devices, the status can be easily checked by navigating to Settings, then System, followed by Storage, and then Disk & Volumes. If the properties section indicates 'Encrypted' under BitLocker, it confirms that the feature is active. Users can disable BitLocker if they wish, although having a Microsoft account or a separate backup of the recovery key mitigates the risk of data loss.

The October 2025 update serves as a timely reminder of the importance of backing up the BitLocker recovery key. Windows provides mechanisms for this, including automatic backup to a Microsoft account. Users can also manually back up their recovery key by accessing Control Panel, then System and Security, followed by Device Encryption, and selecting 'Back up your recovery key.'

Despite some criticism of BitLocker, it remains a vital tool for safeguarding personal files. Microsoft continues to issue updates to address various issues; however, the October update also introduced new challenges, such as problems with Windows Recovery Environment (WinRE), where the mouse and keyboard ceased to function. Microsoft has acknowledged this and released an out-of-band update to resolve the issue.

Furthermore, users have reported that the Preview pane in File Explorer is non-functional after the October update, attributed to a deliberate change by Microsoft to counter NTLM attacks. Additionally, issues with Task Manager have emerged, where users find that it cannot be closed using the standard method of clicking the 'X' button, leading to performance concerns that Microsoft is currently investigating.

As the impact of the October 2025 update unfolds, users are encouraged to back up their BitLocker recovery keys and remain vigilant for further announcements from Microsoft regarding fixes and updates.