Excel addin doesn't work.

[David_2009]

I used VS2005 to create an addin (Extensibility->shared addin, Visual Basic,
all Office products, load when application starts and for all users). Then
just added a simple MsgBox("HELLO") in OnStartUpComplete and OnConnetion.
Built the solution, built the setup, ran the .msi file (Everyone who uses the
computer).

However the message box appears only when I open Outlook, Visio and
Powerpoint. It doesn't show up in Word and Excel. I'm using Office 2003.

Any ideas ?

Thanks.
-david.