Reload this Page VPN by iPhone work but at MacBook doesn't work! why ?

Hello

I use Virtual Private Network.(VPN) L2TP

at iPhone connect and receive data

at MacBook connect but doesn't receive data

what is difference between VPN configure at iOS and OSX ?

For iPhone I did this Instruction :

http://www.strongvpn.com/setup_ios_l2tp.shtml

I Choose "L2TP" tab.

Enter Server, Account, Password and Secret

Send All Traffic should be ON.

and for MacBook I did :

http://www.publicvpn.com/support/MacOSX105.php

I Enter the VPN server’s IP address and user name.

Select Authentication Settings… and then enter the password. enter the shared secret.

the "Send all traffic over VPN connection" check box should be marked.

Where do I mistake ?

Thanks in advance