imac won't stay connected

I recently bought a new wireless router: D-Link dir-615

I set up my macbook pro first and it connected fine, then i tried to get my mother's imac connected which worked, then when i restarted it, it would not connect!

I have to go through the setup thing each time and input the password, even though i had asked it to save the password. really strange! i can see the password in the keychain

any ideas why it keeps reseting?

btw my macbook pro is running tiger 10.4 and my mother has the latest Leopard version

Which type of security are you using for wireless? WEP? WPA? WPA2? If you're using WEP, I suggest you use either WPA or better yet, WPA2.

As for the DLink 615 router, make sure you're broadcasting the SSID (network name) and that your mother's machine has it entered in preferred networks so that it will connect automatically.

Before making any changes to the router, connect an ethernet cable from your machine first so that you do not lose the connection.

Regards.