Frequently Asked Questions
Why are DH groups 1–13 no longer supported in macOS 26 for IPSec?
With macOS 26 Tahoe, Apple has ended support for all Diffie-Hellman (DH) groups below Group 14 in the built-in IPSec VPN client. This includes commonly used groups like Group 2, Group 5, and others through Group 13, which many older VPN gateways and routers still rely on.
These DH groups are now considered too weak by current cryptographic standards, and connections that use them will fail. You may see generic error messages like “No proposal chosen” or failed VPN negotiations with no clear reason.
VPN Tracker 365 continues to support these legacy DH groups, so you can maintain compatibility with older IPSec configurations without needing to update your gateway. Learn how to restore your connection with this step-by-step guide.