Message in Japanese (日本語)
        文字列 '<var>X</var>' を UTF-8 バイトに変換できません: <var>Y</var>
Unlocalized message
        Can't convert string '<var>X</var>' into UTF-8 bytes: <var>Y</var>
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文字列 '<var>X</var>' を UTF-8 バイトに変換できません: <var>Y</var>

Can't convert string '<var>X</var>' into UTF-8 bytes: <var>Y</var>
Search by Google