Sending ibook back if can't find help

Question

please, after two days of tech support with apple and my isp provider AND the local authorized dealer still no connection. i am going to have to send it back.
out of the box, it never has conneceted. everything indicates that it recognized the network but it just isn't connected. i carried it in to the AU and he picked up his network just fine.
i have a built in wireless airport, and a wireless router. i also have an IMAC that is conncected with no problem and a windows PC that is also conncected.
i get a message that my password is incorrect (i know i am typing in the correct one) tried the router password, modem password and the computer password. also message saying, "connection failed" in the set up assistant.
i plugged the modem ethernet directly into the ibook and it still didn't connect but my isp provider insist that it is the set up in the ibook not them.
also, a message saying no conncection.
1. can i set up another network? and go from there?
2. is there something i am not doing that everyone at apple is missing????
3. is there anyway to "tap" into my IMAC without the internet conncection on the IBOOK?
please any suggestions would help. i really don't want to return the ibook but i am running out of people to help me.
thank you in advance,
movie lady.

Answer 1

I have a couple of suggestions for you, depending on what you want to do. I apologize if any of this is a reiteration of what was already mentioned.
First, if you want to hook the ibook right up to the cable modem then you may first have to power cycle the modem. Depending on the cable modem that you are using, and all but a few do this, it will remember the MAC (media access control) address of the ethernet card it was plugged into when it was initialized-- precluding the use of other ethernet cards with the modem. If its of any help power cycling of the modem while it is plugged into the ibook may help with the connection. Otherwise, you may have to contact your ISP and ask them to resend whatever commands they need to in order to have the modem reacquire the MAC address. (Each network device has its own unique MAC address.)
If you want to ibook to connect through the imac via airport and the imac has airport, then you need to open the sharing pane of the system preferences application and enable internet sharing from the imac's ethernet port through its airport card. Set the name of the network to whatever you like and make sure that the ibook can see it. Once you do this, you need to disable the firewall under the firewall tab of the sharing preference's pane in order for the ibook to connect to the internet. (The reason is that the firewall protects the imac on all network ports, not just the one connected to the internet. As such, the imac will reject all information that it does not request from either connection. The trouble here is if the ibook sends a request to the imac for some information from the internet, the imac will reject the ibook's request because, from the imac's perspective it did not generate that request. Alternatively, you can manually configure ipfw, but that's probably overkill for your needs.) After this, you should be good to go.
Third, if you are trying to use a router, then you first need to make sure that its configured properly-- see your documentation for this one because each has its own eccentricities. But a few tips include making sure that the wireless connection for both B & G is on to ensure compatibility, adding all computers to the access control list if you are using one, and ensuring that all the passwords match.
As I mentioned above, you may very well need to power cycle your cable modem, or even worse call your ISP in order to change devices.
I hope this helps.