misc/translator/po/en-GB-messages.po:1399: message catalog has plural form translations... misc/translator/po/en-GB-messages.po:3: ...but header entry lacks a "plural=EXPRESSION" attribute Try using the following, valid for English: "Plural-Forms: nplurals=2; plural=(n != 1);n" misc/translator/po/en-GB-messages.po:3: ...but header entry lacks a "nplurals=INTEGER" attribute