How to Connect Old Telephone Jacks to the Internetby Stephen Lilley
Dial-up Internet service uses regular telephone lines to access the Internet. Because of this, you can use any old telephone jack in your home to connect your computer to the Internet at any time, so long as you're using dial-up and have a dial-up Internet service provider. You do this by connecting your computer to the jack with a phone cable, and then creating a new dial-up connection in Windows.
Connect your computer to the telephone jack in your wall using a standard phone cord, identical to the one you use to connect telephones. The plastic clips on the end of the cord insert into the wall jack and into the phone cord input on the back of your computer.
Click "Start" on your computer.
Choose "Control Panel" from the column of icons on the right side of the "Start" menu and click the "Network and Sharing Center" icon.
Scroll down to the Change Your Network Settings portion of the window. From this section, select the first option, "Set up a New Connection or Network."
Click "Set up a Dial-up Connection." Select the "Next" button at the bottom of the window. Type all of your Internet service provider's information into the boxes on screen. This includes your Internet access phone number, your username and your password. Click "Connect" to connect to the Internet via the telephone jacks in your wall.