You have installed the Apple Internet Router software, which is not compatible with the new Open Transport software in System 7.5.2.
Remove the "Router", "LocalTalk (Built-in)", and "LocalTalk (Modem)" files from your Extensions folder and restart you Power Macintosh.
Article Change History:
22 Aug 1995 - Changed title.
08 Aug 1995 - Made minor technical corrections.
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