If your Mac has a built-in modem, you can use it to get on the Internet using the Point-to-Point Protocol (PPP), which is also known as “dial-up” access. Even if your Internet service provider (ISP) doesn’t specifically offer Mac support, you can still use these steps. Tip: If you use an AirPort base station, connect the phone line to your computer’s modem and complete the steps below first.

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Mac OS X: How to connect to the Internet with PPP (dial-up access) and a modem

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