Introduction
Microsoft has addressed known issues with Always On VPN connections, which were triggered by the September 2026 security updates. This article provides a comprehensive guide on how to resolve these issues, including a permanent fix and a temporary workaround for users who cannot install the preview update. The guide also includes details on the affected protocols and their configurations.
Permanent Fix
Microsoft has released the preview update KB5127936, which fixes the issue affecting Always On VPN connections after installing the September 2026 security updates. The update resolves the problem where affected VPN connections could remain in a Connecting state or fail to connect after an initial connection attempt failed. Subsequent connection attempts could display the error message, 'The specified port is already in use.'
Temporary Fix
For users who cannot install the preview update, Microsoft provides a temporary workaround. IT administrators can mitigate this issue by changing the Always On VPN profile from automatic protocol selection to a single protocol, either SSTP only or IKEv2 only, depending on their environment and configuration. Organizations should select the protocol based on their environment, security, and deployment requirements.
Affected Protocols
The preview update fixes the issue for users who have automatic protocol selection or protocol fallback configured. The affected protocols are IKEv2 and SSTP. Administrators can choose one of these tunneling protocols to prevent Always On VPN failures on affected devices.
Related Issues
Microsoft has also addressed related issues with Remote Desktop connections and game/app crashes caused by recent Windows updates. Additionally, Microsoft urges Entra ID admins to migrate users to passkeys, and warns of SSH flaws allowing root privilege escalation. The article concludes with a recommendation to stay informed about new threats and to use AI tools responsibly.
Conclusion
Microsoft has taken steps to resolve issues with Always On VPN connections and other related problems caused by recent Windows updates. Users can resolve these issues by installing the preview update or following the temporary workaround provided by Microsoft. Stay informed about new threats and use AI tools responsibly to protect your organization and data.