New iBook. Internet sharing to pc not working.

Had an old iBook on Airport giving my pc internet by internet sharing with ethernet port.
Got my new iBook, transfered apps and settings (everything).
Plug the pc in, and no internet or network is detected on the pc.

Any ideas? I've tried turning off and back on the Sharing options in Preferences (on iBook, duh), but with no luck. Comments? Questions? Help!