I encountered this issue when creating some dashboards.  More specifically I was adding a PerformancePoint filter to a webpart page.  It took a short while but I quickly realized the URL being inserted was incorrect:

 

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In fact the path should be something like /PWA/ProjectBICenter/Lists/PerformancePoint Content/8_.000.   Therefore instead of highlighting the PerformancePoint item, then clicking the OK button, simply highlight the item, then select the URL from the Location (URL) path shown below:

 

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Once selected, click the Cancel button, then simply paste into the Location: path in your Webpart Editor:

 

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Now you’ve got it!  Simply click ok and no more error.