From: bbiker <renard@...>
Date: 2006-07-09T13:05:07+09:00
Subject: Re: excel addin

greg.rb wrote:
> bbiker wrote:
>
> > It appears that you first must uninstall and then re-install the
> > addin!!!
>
> Glad you found a solution. Any idea why it behaves this way?
> -Greg

I found this in the description of Installed properly description in
the online Excel Visual Basic documentation.

----- Setting this property to True installs the add-in and calls its
Auto_Add functions. Setting this property to False removes the add-in
and calls its Auto_Remove functions. ---

So my guess is as follows:
If when you set Installed to 1 (True) and Installed is already set to 1
then the Auto_Add functions are not invoked. Likewise setting Installed
to 0 (False) behaves in a similar manner..

you cannot uninstall something that has not been installed.
no point in installing something if it is already installed.

It seems that when Excel is started "normally" the re-installation of
addins is automatic.
Obviously, this does not occur when Excel is invoked via WIN32OLE.