The MacTCP 2.0.4 control panel that ships with Performa computers cannot be updated using the MacTCP 2.0.6 Update installer. You should use the System 7.5 Update 1.0 which includes MacTCP 2.0.6.
The System 7.5 Update 1.0 will install MacTCP 2.0.6 if it finds an older version in the Control Panels folder. Otherwise, you can use the custom install feature in the System 7.5 Update 1.0 installer by following the steps below:
1) Choose Custom Install in the pop-up menu.
2) Click the triangle next to Control Panels to expand these options.
3) Click the checkbox next to MacTCP to select it.
4) Click the Install button.
These articles can help you locate the software update mentioned here:
* "Where To Find Apple Software Updates" -- Lists online services for free Apple software updates.
* "Obtaining Apple Product Support in the USA" -- Lists 800 numbers and online services for software updates, Apple support information, and a subset of the Apple Tech Info Library.
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