Apple has removed the software update for the PowerBook 5300 computer which included System Enabler 1.2.1. This article documents what to install in its place.
In place of the PowerBook 5300 System Software Update with System Enabler 1.2.1, you can use System 7.5 Version 7.5.3 available from the Apple Software Updates Web site at http://www.apple.com/swupdates.