Hi joshduck,
I'm not familiar with WACK issue, but I'm trying to find solution on the forum, another community member met the same situation, and he fix the issue, the post:
http://social.msdn.microsoft.com/Forums/windowsapps/en-US/f87c1fd7-991b-4617-9923-02fc06716abf/error-in-wack
If the question is not resolved, I strongly suggest you can raise this question
in the win 8.1 forum
(you mentioned your system is 8.1) for getting a better support.
Best Regards,
James He
MSDN Community Support | Feedback to us
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