Unknown XML character encoding: foo
There is a problem with the character encoding specified at the start
of this XML document. This may be a typo,
a form other than the preferred one (for example,
utf-8), or just
an encoding that the validator cannot deal with.
Correct the declaration, re-encode the document with an encoding such as UTF-8 or UTF-16 or report the omission if this is a registered character set.
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