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Microsoft Windows 11 September 2026 updates break Always On VPN connections

Service Disruption
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Last updated
Happening score
H score 0
1 unique sources, 1 articles

Summary

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Microsoft's September 2026 Windows 11 security updates are disrupting Always On VPN connections, leaving some enterprise users stuck in "Connecting" or seeing "The specified port is already in use" errors. The issue affects devices that use automatic protocol selection for VPN tunneling and can block access back to the corporate network. Microsoft has posted a temporary workaround that forces SSTP only or IKEv2 only until a permanent fix is available.

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H score0 First: 16.09.2026 23:39 Last: 16.09.2026 23:39 Sources 1

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Latest development: 17.09.2026 11:24

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Open Happening

Timeline

  1. 23.09.2026 14:18 2 articles · 1h ago

    Microsoft Windows 11 September 2026 updates break Always On VPN connections

    Initial Disclosure

    After installation of the September 2026 Windows 11 security updates, some Always On VPN profiles began failing during connection setup. Affected users may see the VPN stay in "Connecting" or return "The specified port is already in use" when the automatic protocol fallback path is used.

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