Word can open multiple instances or multiple files in one instance. It is more efficient if all the documents are opened in the one instance of Word.

When you have a document over 300 pages, it is important that you have minimised the formatting overheads by using styles and very rarely applying local formatting. If your repagination is still an issue then you should change your view to Draft View as this lessens the overhead of repagination (but doesn't completely alleviate it). Follow the link provided in the earlier post by wiganken for other tips to speed up your editing.

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Andrew Lockton
Chrysalis Design, Melbourne Australia