HttpUtility.HtmlEncode only encodes characters that are "reserved" in HTML. For this list, see the first table on this page: http://www.w3schools.com/tags/ref_entities.asp .
In other words, only those characters that may conflict with the basic structure of HTML (for example, <,>, "etc.). No other characters should be encoded if the encoding of the transmitted bytes is defined correctly (for example, using and declaring UTF- 8).
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