/System/Library/Extensions/N-Mon.kext” was installed improperly and cannot be used. Please try reinstalling it, or contact the product’s vendor for an update. ( OK )

New icon for the Vuze client (formerly Azureus...
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/System/Library/Extensions/N-Mon.kext Turns out it was a Vuze torrent program that needed to be uninstalled.  Thanks Dick M.

via Apple – Support – Discussions – MacOSXUpdCombo10.6.4 ….