Why doesn't my VPN work with my new Mac? I used Migration Assistant / Setup Assistant to copy everything from an old Mac to a new one, both running 10.8.4. My VPN connection uses the built-in OpenVPN client, via the Network pane in System Preferences.

The VPN worked before the migration, but after migration it just spins on "Connecting..." for a while before reporting:


  The negotiation with the VPN server failed. Verify the server address and try reconnecting.


I can still ping the VPN server, though.

In Console I see these messages, with some information redacted.

2013-06-18 1:10:33.202 PM configd[20]: IPSec connecting to server vpnhost.example.net
2013-06-18 1:10:33.202 PM configd[20]: SCNC: start, triggered by SystemUIServer, type IPSec, status 0
2013-06-18 1:10:33.325 PM configd[20]: IPSec Phase1 starting.
2013-06-18 1:10:33.367 PM racoon[55678]: IPSec connecting to server 1.2.3.4
2013-06-18 1:10:33.367 PM racoon[55678]: Connecting.
2013-06-18 1:10:33.367 PM racoon[55678]: IPSec Phase1 started (Initiated by me).
2013-06-18 1:10:33.372 PM racoon[55678]: IKE Packet: transmit success. (Initiator, Aggressive-Mode message 1).
2013-06-18 1:10:33.492 PM racoon[55678]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
2013-06-18 1:10:36.494 PM racoon[55678]: IKE Packet: transmit success. (Phase1 Retransmit).
2013-06-18 1:10:36.603 PM racoon[55678]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
2013-06-18 1:10:39.604 PM racoon[55678]: IKE Packet: transmit success. (Phase1 Retransmit).
2013-06-18 1:10:39.717 PM racoon[55678]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
2013-06-18 1:10:42.718 PM racoon[55678]: IKE Packet: transmit success. (Phase1 Retransmit).
2013-06-18 1:10:42.834 PM racoon[55678]: IKE Packet: receive failed. (Initiator, Aggressive-Mode Message 2).
2013-06-18 1:10:43.327 PM configd[20]: IPSec disconnecting from server 1.2.3.4
2013-06-18 1:10:43.327 PM racoon[55678]: IPSec disconnecting from server 1.2.3.4
2013-06-18 1:10:43.331 PM racoon[55678]: IPSec disconnecting from server 1.2.3.4
It turns out that Migration Assistant doesn't copy the VPN shared secret, if any. So if that's what your VPN connection uses, go to System Preferences &gt; Network &gt; (your VPN) &gt; Authentication Settings... and set the correct value for the shared secret. Then Apply and try to connect again.