Cisco VPN client version 4.9.01.0290 does not work on OSX 10.7.4 but it works on 10.7.2. The issue is that x64 are not supported. I am not sure way it is working on another mac with OSX 10.7.2, which is still Lion and it is x64. I tried to reboot in 32bit but it does not work anymore. I tired other clients, including the in-built client but the decrypted shared key have characters that are known to break the key ($ and &).
That’s the bad news.
The good news is that you should be able to configure the VPN connection directly within OS X without installing VPN Client. The other end will have to provide you connection information and possibly a certificate file, but that should be easy enough. Detailed information can be found in Cisco’s documentation.
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