Windows – Document Map in MS Word 2007 going bonkers

I’m working on a large project report in Microsoft Word 2007 and have been using the document map to generate the index. I have been carefully selecting the headers that need to be added to the document map,
but I saved the document and opened it up today to work on it –
the document map has added whatever it pleases there.

The following is a temporary fix from a post that I found
^{(The above image is also copied from that page)}
after extensive searching that works,
but when I save and close the document and open it up again
I face the same dilemma:

I have noticed that when Word stuffs
up the document map after opening the
file, I can undo this by using the
UNDO button. Word calls it ‘Autoformat’.

I have also fixed a file that has had
the document map screwed permanently
(i.e., saved with it) by selecting all
(Ctrl+A), selecting the PARAGRAPH drop
down menu in the HOME TAB and in the
OUTLINE drop down box, selecting ‘Body Text’.
This removed all the problems
and did not seem to affect my outline
level paragraph headings.

This is also another temporary fix, but I have to be on my toes not to let Word auto format at the start of the document. I also can’t afford to entirely turn off auto format as I need it.

I’ve solved this problem for me.

When you open the file, a progress bar
at the bottom first says Opening (ESC to Cancel)
and then it says Word is
formatting the document (ESC to Cancel).
If I cancel the second
process, TOC fine. No cancelling, TOC screwed.

Now, can anyone work out how to switch off the autoformatting?