After attempting to repair your Office (which version do you have?) and you get no love; you might try disabling your AVG completely and see if it works. AVG is known to have this problem with Clip Art and has since version 2003. In fact the College I used to teach at got rid of it for this very reason along with others. If disabling the AVG work, and your Clip Art is again accessible I'd suggest you REMOVE the AVG from your computer and replace with a quality AV such as Avast or Norton or McAfee?
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