You'll need a section break at the end of the document you're inserting as
well. See http://word.mvps.org/FAQs/Formatting/WorkWithSections.htm

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Suzanne S. Barnhill
Microsoft MVP (Word)
Words into Type
Fairhope, Alabama USA
Word MVP FAQ site: http://word.mvps.org
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> In Word 2000, I need to insert a new doc at the bottom of my original
> doc and want this second doc to keep all its original formatting. I
> first inserted a break (Insert | Break | choose Next Page radiobutton),
> then inserted my doc (Insert | File). The second doc kept its own
> header but not its Page Margins. How can I force that? Thanks.