Macintosh: No Internet After Installing KeySpan USB to Serial Adapter

My internal modem no longer functions after installing the Keyspan USB Serial Adapter. Can you help?
Note: This issue applies to any Macintosh equipped with USB and an internal modem, including the iMac, Power Macintosh G3 (all varieties), Power Macintosh G4, PowerBook G3 Series, and iBook.

The Keyspan USB Serial Adapter software registers additional ports with Mac OS. The Modem control panel preferences are not properly updated to reflect the additional serial ports so the wrong port can end up being selected.

To resolve this issue, simply edit the currently active Modem control panel configuration with the correct settings for your internal modem. To do this:


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Published Date: Feb 20, 2012