TOA disappears when regenerating TOC

We have Word 2003 document with a Table of Contents and a Table of
Authority. When we regenerate the TOC using the option to Update Entire
Table, the TOA disappears. However if we choose "Update Page Numbers Only"
the TOA remains okay. What is happening here?
Thanks
Ardell

You probably inserted the TOA field inside the TOC field. Press Alt+F9
to switch to display of field codes. For the TOC field, you should see
something like:

{ TOC \o "1-3" \h \z \u }

and my guess is that buried somewhere between the pair of curly braces
for the TOC field are another pair of curly braces for the TOA field.
Just move the TOA field outside of the TOC field braces.

Ardell wrote:

We have Word 2003 document with a Table of Contents and a Table of
Authority. When we regenerate the TOC using the option to Update Entire
Table, the TOA disappears. However if we choose "Update Page Numbers Only"
the TOA remains okay. What is happening here?
Thanks
Ardell