Its very hard to say what might be the problem without seeing your XML (other than to say that there is an error in the XML).
Like Vijay says, common errors are unescaped '&' symbols in your text, but if you are writing the Xml using the same code as you are reading it with this shouldn't be a problem (only if you are writing the XML manually, or through simple string manipulation).
/- Sam Judson : Wrox Technical Editor -/
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