Depending on your OS and your modem. XP Has OEM drivers for alot of different 56k modems. If your not running XP, chances are you'll also have to reload the drivers for your modem before you'll be able to get online. Even if you have XP, I'd suggest going online and downloading the drivers and burn them to disk prior to reformatting your drive, unless you have the installation disk that came with the modem.