Personal Organizer and printer port errors

Ivan Ivancin found that the Personal Organizer 3.03 Listener extension prevented his Epson Stylus Color 740 from printing via a serial connection. When trying to print, an error message appeared that said: "The Printer port you want to use for SC 740 is not available because AppleTalk is selected or another application is using the port. Use the Chooser to disable AppleTalk, close the other application, or use the modem port." Turning AppleTalk on or off had no effect. Disabling Organizer Listener and restarting worked-around this glitch. Skip Press had the exact same symptom when trying to print to his Color StyleWriter 2500 after installing Personal Organizer 3.03.