I had this “There are too many edits in the document. This operation will be incomplete. Save your work.” problem, too. I found nothing on the internet or MS help pages to help solve it, until a co-worker suggested that I download OpenOffice.org Writer, open the document and save it as another document name. This suggestion proved successful in allowing me to again use MS Word to make further changes. I’m not sure what changed internally in the document or how long before I encounter this error again, but for now I’m back to work. Maybe this adds fuel to the OpenOffice vs MS Office debate 😉