Bonjour,

Problème résolu!!!
Il ne manquait qu'une manip :


First, set up the mac. From the apple menu, go to:
>System Preferences
>Network
in the "Show" bar
> Built-in Ethernet
in the Configure bar
> Using DHCP

Now hook an ethernet cable from the mac to the router. Do not
connect the router to the DSL modem. If you have done so already,
unhook that cable. You can do this before the network config just
above if you like. But make SURE the router and the modem are
not connected together.

At this point, your computer should be talking to the router. The
Network window should show an IP address of the form 192.168.1.x
where x is 2 or a small number. Anything from 2 to 255 should be OK.
More importantly, the router should read 192.168.1.1. If this isn't
happening, click on the "Apply Now" button. If that doesn't help,
try the "Renew DHCP Lease" button. Once you have a router address,
you can proceed.



Désolé de vous avoir ennuyé avec cela.
Je vous remercie encore d'y avoir consacré du temps.