Häufig gestellte Fragen

If your IPSec VPN connection stopped working after upgrading to macOS 26 Tahoe, the issue is likely related to Apple’s removal of legacy encryption and authentication algorithms in the built-in macOS VPN client. The update no longer supports older algorithms such as DES, 3DES, SHA1-based authentication, or outdated DH groups, which many IPSec configurations—especially on older firewalls and routers—still rely on.

These changes result in error messages like “No proposal chosen” or failed connection attempts with no further explanation. Affected devices include older models from vendors such as Cisco, SonicWall, Fortinet, and others.

VPN Tracker 365 still supports these legacy IPSec configurations, allowing you to restore your connection without modifying your existing VPN gateway settings. Follow this step-by-step guide to get your IPSec VPN working again.