Outlookthe most featured host application

Add-in Express encompasses and broadens much of the Outlook Object Model through our own Extensibility API and Outlook-specific components and classes, such as:

  • Explorer and Inspector "aware" toolbars and menus
  • Outlook-specific Fluent UI customization
  • Built-in task panes in Outlook 2007 - 2021/365
  • Version-neutral view and form regions
  • Custom task panes
  • Solution modules in Outlook 2010 - 2021/365
  • Option and property pages
  • Navigation pane shortcuts
  • Binding your UI to Outlook folders, content and context
  • Handling application, folder and item level events

Outlook is the most popular Office application

Today, Add-in Express is used to build solutions for all Office applications. However, everything grew from a humble foundation of an internal framework for programming Outlook extensions only. Yet Outlook still remains the most featured Office application supported by Add-in Express and the most popular host application among our customers.