However, when I look on WordXP, there are two windows with _Wwf as their
class.

What is this reason for the differences in Window structures between the two
computers?

Is it due to the version difference?  Or put in a different way, can I count
on there being two frames in Word XP and only one frame in Word 2000?

Or is it due to some other setting that is different between the two
computers.

I would guess the difference is between Word 2000 and XP and not the
computers. I don't know which windows are using the _Wwf class but you have
one GUI difference between '2000 and XP, XP has a task pane. It can be that
the task pane shares the characteristics with the doc window.

I don't know how deep you have been into WinAPI when it comes into cretaing
windows/controls, but if you haven't been there I can explain very breifly
how it usually works when you don't use a predefined Window Class. First you
call WinAPI RegisterClassEx() and pass information like Class name, function
pointer to a 'Window Procedure', Icon, Cursor, Background and some other
characteristics. When you want to create the Window you call
CreateWindowEx()  and pass information about the Class it will be based on,
size, style and other information. Even though two Windows can appear quite
different they can still be be based on the same registred Class. If the doc
window and the task pane are based on the same Class it would explain why
you find two Windows based on the same Class in Word XP. I might be wrong
but it's something like this I would suspect.
--
Regards,
Lars-Eric
http://www.clippersweden.se

Word New User FAQ & Web Directory:
<URL: http://addbalance.com/word/index.htm>

Intermediate User's Guide to Microsoft Word (supplemented version of
Microsoft's Legal Users' Guide)
<URL: http://addbalance.com/usersguide/index.htm>

See also the MVP FAQ: <URL: http://www.mvps.org/word/> which is awesome!
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