G5 airport issue

My girlfriend has an imac G5 which recently had a catastrophic disk failure. My stepdad was able to fix it and when he fixed it he upgraded it to Leopard. Since updating it to leopard she can no longer connect to the free wireless in her building. It's an unsecured netgear router. It prompts her for a password even though it isn't secured. She can connect to secured connections just fine. When she was running Tiger this wasn't an issue. It connected just fine. In the PC world I would just assume to roll the driver back. I do not know how to do this on a Mac and would like a little help, or if there is a completely different procedure. She also has a black macbook that suffers from this as well. Any help would really be appreciated.

Free wireless in the building. OK. You mentioned an unsecured wireless Netgear router. Where is it located? Is it in your girl friend's apartment?

Anyway, it probably has nothing to do with drivers. Open up System Preferences, Network on her machine. It should say (highlighted) Airport Connected.

Make sure the network name is displayed. Now click on the Advanced button in the dialog below. The Airport tab on the top menu should be highlighted. Again make sure the network name is displayed in the box below and it should say unsecured. If not, you'll need to change it.

Now click on the TCP/IP tab on the top menu. Make sure the machine is using DHCP. Click on the DNS tab on the top menu. Check to see that the correct DNS addresses are listed.

OK your way out of the menus and reboot the computer. If everything is alright, she should be able to connect.

BTW, using an open wireless network in an apartment building or anywhere else for that matter, is not recommended. Tell your girl friend not to discuss or give credit card info, her bank info, or any sensitive info over the net.

Regards.