Try using Ctrl-A, F9 to force all fields to update. If your TOC doesn't pick up the new entries, there are two main possibilities:
1. The omitted headings aren't formatted in the Styles used by the TOC (typically 'Heading 1', 'Heading 2', 'Heading 3'); and/or
2: The TOC has a bookmark switch, telling it to only pickup headings in the portion of the document spanned by the bookmark and the omitted headings aren't in that portion of the document.
Cheers
Paul Edstein
[MS MVP - Word]