I know this has a simple fix, but the error message might not be too clear to some people. If you try to use Linq to XML you must first start off by adding a using statement for System.Linq.Xml. This is very easy to do... Just write the initial XDocument, with the right casing, and then press "Ctrl+." and then enter. This will add the using statement and you can keep going. So you start writing your query but it doesn't work.
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