Cannot Dial Up With Aol!!!

I just got my dad a 400 mhz blue and white G3. He has OS 10.2.8 installed, and he is trying to use the latest AOL disc for dial up. He is getting an error message when trying to use the dial up. It will not allow him to dial up via GUEST. He wants to add his existing AOL account, but he tells me that it will not let him. I have done some Google searches, but can't really find any suggestions. Please let me know if you have any suggestions, and if he needs to change any configurations in the Network panel. Thanks for any help you may have.