I struggled with that on Office 2003 too. In the end I had to use google to see how others worked around this. I can't remember the exact fix but let me share ONE IMPORTANT THING I DID.
I made a backup copy (actually I made three!) and that let me try more than once.
Bob
Help, has the world gone mad? I am having a problem with editing Word docs in Microsoft Office 2997. When I have tracked changes, accepted them all, & requested to see only the final copy, I turn off the tracking & save the doc. When I reopen it, all the markups show up. This is huge inconvenience when I need to provide the final docs to someone. This never used to happen. What changed? What am I doing wrong?
I have a 64 bit HP Q6600 2.4 GHz computer, with Windows 7. Previously had Vista, but think I noticed problem before I installed this.

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