I have produced a number of quite large workbooks for use by students.


They are protected with access only to input areas.
Trouble is, sometimes, where the Word 2013 document is opened in other versions of word, or even the same version on another computer, Word re-interprets the styles, often with disastrous results (eg: content which was 10 pt becomes 18 pt).
I have connected the documents to their own template which contains the styles I want, but the chaos continues.
Is there a way I can embed the styles into the documents so, no matter where they are opened, they only use the styles contained in the original?

Your description suggests your distributed document most likely has the 'Automatically update document styles' attribute checked. See under Developer|Document Template. Unchecking that option should resolve the problem.

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Cheers,
Paul Edstein
[Fmr MS MVP - Word]