Deploy Office addin: Windows Installer,
WiX setup project, InstallShield

Add-in Express™
for Microsoft® Office and .net

Deploying Office add-ins

Add-in Express provides the maximum flexibility for your Office installations supporting several installation types and deployment models:

See related videos:

Table 1. Deployment technologies. Short descriptions.

Windows Installer (.msi)	You create a regular .MSI installer to install per-user and per-machine Office extensions. To update your Office extension, you uninstall its current version and install the new one. A per-user add-in is installed by an end user; a per-machine add-in requires administrative permissions.
ClickOnce	This technology is targeted at non-admin installations; only per-user Office extensions can be installed in this way. When the user updates your Office extension, its previous version is uninstalled automatically.
ClickTwice :)	This is a custom MSI-based Web deployment technology. ClickTwice :) allows standard users and admins to run MSIs from the web (Internet and Intranet) for installing and updating per-user and per-machine Office extensions.

Table 2. Deployment technologies. Detailed Comparison.

Feature	ClickOnce	Windows Installer	ClickTwice :)
Update from the web	Yes	No	Yes
Post-installation rollback	Via Add/Remove Programs	No	No
Security permissions granted	Grants only permissions necessary for the application (deploying COM add-ins, it always requires Full Trust).	Grants Full Trust by default	Grants Full Trust by default
Security permissions required	Internet or Intranet Zone (Full Trust for CD-ROM installation)	Standard user or Administrator	Standard user or Administrator
Installation-time user interface	Single prompt	Multipart Wizard	Multipart Wizard
Installation of shared files	No	Yes	Yes
Installation of drivers	No	Yes (with custom actions)	Yes (with custom actions)
Installation to Global Assembly Cache	No	Yes	Yes
Installation for multiple users	No	Yes	Yes
Add an entry to Start menu	Yes	Yes	Yes
Add an entry to Startup group	No	Yes	Yes
Add an entry to Favorites menu	No	Yes	Yes
Register file types	No	Yes	Yes
Install time registry access	HKEY_LOCAL_MACHINE (HKLM) accessible only with Full Trust permissions	Yes	Yes
Binary file patching	No	Yes	Yes
Installation location	ClickOnce application cache	Changed by the user during the installation	Changed by the user during the installation