Problem connecting iMac and MacBook to same wireless network

[otep1760]

So a friend of mine just bought an iMac and is trying to use it on her wireless network. Before the iMac was bought she could use the wireless network I. Her house fine but since the iMac got hooked up the computers can't be online at the same time.

If the MacBook is on and the iMac is off the Internet works on the MacBook and vice versa. Is there anyway a firewall is preventing both computers from connecting to the same wireless network? If so, is there anything you can do to help me out to get them both working properly?

A netgear router that was provided by time warner is being used and I'm not sure if y'all need anymore information than that.

Anything helps. Thanks

 

[BlueRevolution]

Did she use Migration Assistant to copy the system across between computers?

On each computer, go into System Preferences -> Network -> AirPort -> Advanced -> TCP/IP -> Configure IPv4 -> (set) Using DHCP.

Does that help?

 

[JediMeister]

Sounds to me like both computers were set up using the same static IP address. So whatever computer gets powered on last is what is able to connect to the internet. Blue's solution should work but making a new network location is also an option. On the main network preferences window, under the dropdown menu next to Location will be options for New Location or Edit Locations. Create a new location, select the AirPort connection and then make sure its set to get an address from the router via DHCP. Click apply in the lower right, wait for the IP address, subnet, and router addresses to populate. If your friend gets an address other than 169.254.x.x chances are she'll be able to go online.

 

[otep1760]

Thanks for all the help guys, I will try them out in a bit when I get off work and let you know how it goes.
Thanks again!