Still duck eggs.  The problem appears to be in my VB Editor.  I am in deep
water here and hardly know what I am talking about.  However, if I add a
second TOC and run this code:

Sub MacroTest()
Dim i As Long
For i = 1 To ActiveDocument.TablesOfContents.Count
ActiveDocument.TablesOfContents(i).Update  '****
Next
End Sub

And then step though, I get to the the line tagged **** and the macro just
terminates.  For some reason the line of code is not being executed.

Is it OK if I start foaming at the mouth now :-)

Anne and anyone else following.

It appears I have stumbled on a cause of the problem yet still can't
understand it.  As it turns out I was having the same problem at work
using Word2000.  The only thing common with my work computer and home
computer is my Normal.dot

First I am guilty of sloppy housekeeping with my normal.dot  (Any
suggestions for changing my ways are welcome.)  I have about 10
different modules in my Normal.dot and probably a hundred or more
macros.

I created a new Normal.dot and all worked as expected.

Next exported all of my modules from the NormalOld.Dot to the desktop.

Next I imported the modules into the new normal.dot one at a time
checking functionality of the TOC update each time.  The problem
reoccurred when I imported one of the modules.

I started looking at the individual macros in that module.  I found
that the following macro was causing the behavior:

'Sub UpdateFields()
'Dim oStory As Range
'  For Each oStory In ActiveDocument.StoryRanges
'      oStory.Fields.Update
'   If oStory.StoryType <> wdMainTextStory Then
'   While Not (oStory.NextStoryRange Is Nothing)
'       Set oStory = oStory.NextStoryRange
'       oStory.Fields.Update
'   Wend
'   End If
'  Next oStory
'Set oStory = Nothing
'End Sub

When I stetted in out as show above the first time I ran the TOC update
routine I got and Error something like "Could not find sub or funtion).
It was like the line
ActiveDocument.TablesofContents.Update was trying to run the
UpdateFields() routine above.  I close the VBE and reopened it and the
TOC routine then ran fine.  I have since renamed the macro above as
myUpdateFields all is working properly at least on the Word2000 PC.