Word Takes Ages to Close a Document
The Problem:
The longer I've been working on a document, the longer Word takes to close it. And if I use Save As to save the document under a different name, it takes even longer to close.
The Solution:
Sorry, there's no fix for this problem, other than shortening your sessions with any particular document. What's happening is that Word is disposing of the temporary files that it has created while you've been working with the document. Word is also clearing out of its Undo buffer the data for the undoable actions in this document. (It leaves the data for any other documents that are open.)