A family of Microsoft word processing software products for creating web, email, and print documents.
Thanks, Stefan. I'm going out of town for a couple of days, so I'll check this when I get back.
It does occur to me that I slightly misrepresented the problem. The system treats me as a different user at first (with a new color for my new edits), but as I go along and hit 'save', the color changes to the color of the old edits. So when I wrote 'Track changes function thinks I'm two people', that's not quite accurate. It's more that for some documents, the track changes function tracks my own editing history. I.e., it recognizes that I'm the same user (because ultimately it puts all my changes in the same color), but it still treats old changes as set somehow, so that deleting my old additions makes them show up as deletions.
As I said, I'll check what happens now that I've ticked that box when I return on Wednesday. Thanks.