Add-in Express shares all regions between all forms created by all loaded add-ins that are based on the Add-in Express technology. Since one Outlook region can contain several forms, the provided region header allows users to navigate between all forms hosted by the region. By default, the region header displays a list of hosted forms and Forward / Backward buttons that activate the next and prior forms. In addition, the region can display a Close button that closes the active form.

End-users can easily resize, minimize or hide your regions. Using the splitter incorporated in your region, the end-user can resize your region. Double-clicking on the splitter hides the region. The splitter may include the Hide button, which hides the region (double-clicking on the splitter does the same). The region header contains the Minimize button, which minimizes your region. The splitter and the Hide / Minimize buttons can be individually disabled. This ensures that your region cannot be resized or hidden / minimized.

Add-in Express Regions supports the following instancing strategies: Creating a new instance for each folder and destroying it when the end-user switches to another folder. Creating a new instance for each folder and adding it to the forms cache when the end-user switches to another folder. Creating one instance for all specified folders.