Science & Tech · Big Tech & Internet · 1 hr ago
Microsoft fixes Always On VPN failures after September Windows updates
Microsoft has fixed an Always On VPN connection problem caused by September 2026 security updates.
The issue affected Windows 11 version 24H2 and later, when an initial VPN connection attempt failed.
Always On VPN automatically creates a secure connection between a device and its organization’s network when the device goes online.
Affected connections could get stuck or fail, and some later attempts showed an error saying the port was already in use.
Microsoft released updates KB5127648 and KB5127646 to address the problem on affected systems.
Organizations unable to install the updates can choose one VPN protocol—SSTP or IKEv2—instead of automatic selection.
Administrators should choose the protocol that fits their network and security needs.
Microsoft has fixed an issue that caused Always On VPN connection failures after September 2026 Windows 11 security updates.
The problem affected up-to-date systems running Windows 11 24H2 and later when an initial connection attempt failed.
Microsoft released the KB5127648 and KB5127646 cumulative updates to address the issue.
As a temporary workaround, Microsoft advised administrators to configure the VPN profile to use either SSTP or IKEv2, rather than automatic protocol selection.
- Who
- Microsoft and organizations using Always On VPN on affected Windows systems.
- What
- Microsoft released updates to fix connection failures after an initial VPN connection attempt failed.
- When
- The issue followed the September 2026 Windows updates; Microsoft released the fixes on Tuesday.
- Where
- On affected Windows 11 systems, including Windows 11 24H2 and later.
- Why
- The September updates triggered a bug involving automatic protocol selection or protocol fallback when an initial connection failed.
This story does not have two clearly opposing sides.
Microsoft acknowledged the Always On VPN issue in a service alert to IT administrators.
Microsoft released the KB5127648 and KB5127646 cumulative updates to address the issue.
- Affected systems
- Windows 11 24H2 and later
- Fix updates
- KB5127648 and KB5127646
- Temporary workaround
- Configure the profile to use SSTP only or IKEv2 only
- Trigger
- An initial VPN connection attempt fails with automatic protocol selection or protocol fallback enabled
What people are saying
When automatic protocol selection or protocol fallback was configured, affected VPN connections could remain stuck in a Connecting state or fail to connect after an initial connection attempt failed,
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.