Frequently Asked Questions
Does macOS 26 still support SHA1-based algorithms for IKEv2 VPNs?
No — with macOS 26 Tahoe, Apple has removed support for SHA1-based authentication algorithms in the built-in IKEv2 VPN client. This includes both SHA1-96 and SHA1-160, which were commonly used in older VPN configurations.
These algorithms are no longer considered secure and can lead to connection failures with messages like “IKEv2 negotiation failed” or “No acceptable proposal found.” Unfortunately, macOS 26 offers no option to re-enable SHA1 support.
VPN Tracker 365 still supports SHA1-96, SHA1-160, and other legacy algorithms, allowing you to keep using your existing VPN setup without modifying the gateway. Follow this step-by-step guide to restore compatibility.