A menos que intente convertir un nuevo documento en uno anterior, debería ver las opciones de compatibilidad para su Microsoft Word.
Windows tiene muchas opciones de compatibilidad. Puede consultar su sitio de ayuda para ver si su pregunta está incluida en el Centro de ayuda o en los foros.
Ofrecer más detalles nos ayudaría. Danos las soluciones que probaste.
Puede instalar EQ 3.0 para editar ecuaciones en palabras antiguas. Elija EQ 3.0 en el objeto. Si desea realizar una conversión completa, deberá utilizar un software de terceros.
Solution: The default format for Word 2007 files, DOCX, creates a compressed group of XML (Extensible Markup Language) files, each of which contains information about the document. It is incompatible not only with earlier versions of Word, but also with other programs that have previously been able to open Word files.
Users of Word 2003, 2002, or 2000 can open Word 2007 files if they install the Microsoft Office Compatibility Pack. (Visit www.microsoft.com/downloads and search for Microsoft Office Compatibility Pack For Word.)
Optionally, you can use the Save As option to save files in DOC format, which is compatible with Word 97 to 2003. Users of other programs can use a file converter such as Zamzar (free; www.zamzar.com).
To enable users of previous versions of Microsoft Word to read your Word 2007 documents without a special download, save them in Word 97-2003 format. If you used features unique to Word 2007, such as themes, citations, and equation building, in your file, these elements will not come through as expected during format conversion, and some information may be lost permanently. Word 2007 will restore as many features as possible when you reopen a converted file, but it cannot restore all lost formatting. If you want to keep all functionality, save two versions—one for Word 2007 and one for users of other versions.
Fuente: http://www.uvm.edu/~bnelson/computer/word2003/whenisaveafileinmicrosoftword2007olderversionsofwordcannotopenthem.html
Mathtype es un programa comercial para convertir ecuaciones en más de 500 formatos.
Está bien alabado. He visto muchas referencias a este programa para tratar los problemas de compatibilidad de Word.
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