In the Control Panel:
[Settings]

Select group ---» Registration
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Under the “Options” menu
Member modules ---» Pictures ---» Comments
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Member modules ---» Videos ---» Comments
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Member modules ---» Blogs ---» Comments
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Member modules ---» Guestbook
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Member modules ---» Events ---» Comments
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Under the “Options” menu
Content modules ---» Select group ---»  News
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Content modules ---» Select group ---» Feedback
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Content modules ---» Select group ---»  Friend Invites
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Content modules ---» Select group ---» Custom pages
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