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When you right-click on your project's root directory and click "Properties" in the resulting contextual menu, you'll get the "Properties for [ProjectProjectName" dialog. Click "Java Build Path" in the left navigation pane and then click the "Libraries" tab. You can remove the entries for "xalan.jar" or "xalan-2-6-0.jar" and "xercesImpl.jar" and "xml-apis.jar" from your build path. On the "Order and Export" tab, ensure that the JRE comes before tidy.jar (as in the order described in the XML above.)
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