In many cases a software control panel extension creates this conflict. The LaserWriter Bridge software by Sonic Systems is a control panel which is provided with the LaserWriter Select 360 printer and is probably preventing the printer port configuration from being changed unless AppleTalk is turned off first. The LaserWriter Bridge software resides in the control panels folder and allows a networked LocalTalk device such as the LaserWriter Select 360 to be visible on an Ethernet network. Apple ships the LaserWriter Bridge software with all LaserWriter Select 360 printers so it is possible that the LaserWriter Bridge was installed on one or more of these systems. The software can be turned off from within the control panel itself, but the system must be restarted for the changes to take effect. If the LaserWriter Bridge software features are not required then simply turning it off from within the control panel will allow the printer port to be used with the Color StyleWriter 2400, Color StyleWriter Pro, StyleWriter II, and other serial based printers.
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