Read add-ins are Outlook add-ins that are activated in the Reading Pane or read inspector in Outlook. Unlike compose add-ins (Outlook add-ins that are activated when a user is creating a message or appointment), read add-ins are available when users:
View an email message, meeting request, meeting response, or meeting cancellation.*
View a meeting item in which the user is an attendee.
View a meeting item in which the user is the organizer (RTM release of Outlook 2013 and Exchange 2013 only).
Note Starting in the Office 2013 SP1 release, if the user is viewing a meeting item that the user has organized, only compose add-ins can activate and be available. Read add-ins are no longer available in this scenario.
- Outlook doesn't activate add-ins in read form for certain types of messages, including items that are attachments to another message, items in the Outlook Drafts or Junk Email folder, or items that are encrypted or protected in other ways.
In each of these read scenarios, Outlook activates add-ins when their activation conditions are fulfilled, and users can choose and open activated add-ins in the add-in bar in the Reading Pane or read inspector. Figure 1 shows the Bing Maps add-in activated and opened as the user is reading a message that contains a geographic address.
Figure 1. The add-in pane showing the Bing Maps add-in in action for the selected Outlook message that contains an address
Types of add-ins available in read mode
Read add-ins can be any combination of the following types.
API features available to read add-ins
For activating add-ins in read forms: see Table 1 in Specify activation rules in a manifest.