Converting between Word versions has never changes page sizes or margins. I have no idea what gives you the idea it can. Likewise, regardless of whether a document has manual page breaks or paragraph-formatting page breaks, the result for the printout is the same. Changing them is not a magic bullet. The idea that a change in measurement units from inches to mm can change things is likewise nonsensical - those are display measurements only (Word actually works in twips behind the scenes). In any event, nothing of what you posted addresses the OP's issues. Whether you think my response very friendly concerns me a world less than steering the OP away from ill-informed misdirection.

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Cheers,
Paul Edstein
[Fmr MS MVP - Word]