I had a TOC that was working fine. Now, when I update it, additional tab
stops get inserted so that the page numbers are no longer right aligned, and
the leading ... disappear. I can clear the additional tab stops in Format |
Tabs..., but when I update again they are reinserted.

I looked at mvps.org, and tried the suggestions (including the macro) from
the article "...update my TOC it acquires unwanted tabs, and I have to press
Ctrl+Q to get rid of them", but this actually worsens the situation, removing
the tab stop at 6.43 inches that seems to be what is required for the TOC to
look right.

Unfortunately I made a number of changes to the document in between the Toc
working properly and not, so I can't narrow down from that direction.