The defragmentation component of the tune-up uses the system defragmenter, but limits its run time, so it often fails to complete. The informational message you’re seeing is thus normal. There isn’t any way to get a complete defragmentation from within OneCare, but running the defragmenter from the system will provide a full defragmentation, and thus allow the tune-up defragmentation component to “catch up” on its work. Click Start, select All Programs, select Accessories, select System Tools, and click Disk Defragmenter.
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