My Dad is currently unable to connect to the Internet with his Mac and I'm hoping someone here will be able to help.

He's using Mac OS X Version 10.4.11. It connected fine this morning but he's been unable to connect this afternoon or this evening. A message keeps popping up saying: "Could not find a PPPoE server". I've tried running through the wizard for setting up the connection but it doesn't seem to work.

I've been using my PC online all day with no problems.

Please can someone suggest what I need to do to get it connected again?