Hello John,
1. Both VSTO and the Shared Add-in wizard create add-in projects based on
the PIAs version (= Office version) installed on your PC. They will work
with higher Office versions because they are almost 100% compatible with
older ones. To access properties and methods of a higher Office version, you
use late binding. To access events of a higher Office version, you will have
to study PIAs via .NET Reflector and write a similar code.
Add-in Express creates projects based on Office 2000 regardless of the
Office version you have installed on your PC. Also, you can use the version
installed. To access properties and methods of a higher Office version, you
use late binding. To access events of a higher Office version, you use the
version-independent Outlook Events component and a number of
version-independent Outlook Event classes. The default behavior of command
bar and ribbon components in Add-in Express allows you to create one add-in
that will show command bars in pre-2007 versions and Ribbon tabs in Outlook
2007.
2. VSTO, Shared Add-in, and Add-in Express create setup projects
automatically. However, Add-in Express adds an appropriate pre-compiled
setup action, depending on the shim type you use: non-isolated (that's the
shared add-ins way), VSTO Loader, or Add-in Express Loader. See shims
compared at
http://www.add-in-express.com/docs/net-deploying-addins.php.
Add-in Express provides a unique feature: ClickOnce deployment for add-ins
(see
http://www.add-in-express.com/docs/net-clickonce-solution.php). This
technology allows a non-admin user to install an add-in from a web-site. See
an introductory notes on ClickOnce at
http://www.add-in-express.com/docs/net-clickonce.php.
3. The user can unload the add-in via the COM Add-ins dialog. In Outlook
2003, you can find it in the menu Tools | Options | Other | Advanced Options
| COM Add-ins. To add this item to a command bar see
http://www.add-in-express.com/forum/read.php?FID=5&TID=1094.
Regards from Belarus,
Andrei Smolin
Add-in Express Team Leader
www.add-in-express.com