Microsoft warns Windows 11 users to ensure Secure Boot certificates are updated before the June 2026 deadline; Devices on older Windows versions may be left vulnerable.

Microsoft advises Windows 11 users to ensure their Secure Boot certificates are updated before the looming June 2026 deadline. The certificates, integral to Windows' security architecture, are set to expire, prompting the need for users to verify their devices' status and apply necessary updates.

The expiration timeline is critical, with industry guidance suggesting that late June 2026 marks the start of this window. Users on older Windows versions, many of whom are already facing restrictions, may find themselves locked out of future boot-level security features, significantly increasing their vulnerability. Approximately 400 million PCs are estimated to be impacted due to hardware requirements that have already excluded them from Windows 11.

With Windows 10 support officially ending in October 2025, Microsoft had previously introduced an Extended Security Update (ESU) program to help bridge the gap. However, only enrolled Windows 10 PCs will receive the new Secure Boot certificates, emphasizing the urgency for users to check if they are eligible or if they need to pursue manufacturer firmware updates.

As the technology landscape evolves, the importance of timely software and security updates cannot be overstated. Users are urged to take proactive measures to maintain their device's security and compatibility.

Microsoft has warned Windows 11 users to update their Secure Boot certificates before the June 2026 deadline, as older Windows versions could be left vulnerable. Devices not receiving updates may lose essential security features, putting millions at risk after Windows 10 support ends in October 2025.