How Teams Makes Webinar Information Available for Search and eDiscovery

Partnership with Microsoft Lists Does the Trick

In an earlier article, we cover how Microsoft makes the spoken words in Teams meeting recording transcripts available to Microsoft Search. A similar approach is used to make the attendance for Teams webinars available to Search. Here’s what happens.

Webinars are calendar events, so their existence is recorded in the meeting organizer’s Exchange Online calendar. Also, The Microsoft 365 substrate captures meeting details in items in a hidden folder called 93c8660e-1330-4e40-8fda-fd27f9eafe10AttendanceReportV3Collection in the non-IPM part of the organizer mailbox, including JSON-formatted information about meeting participants captured in the ArtifactEntriesJsonBlob property (Figure 1).

Attendance data for a meeting captured in a meeting organizer's Exchange Online mailbox
Figure 1: Attendance data for a meeting captured in a meeting organizer’s Exchange Online mailbox

This information is captured for all meetings (including webinars) and is used to display the attendance report for the event in the Teams calendar app. Figure 2 shows the attendance report based on the information captured in the record shown in Figure 1.

Attendance report for a very short Teams meeting
Figure 1: Attendance report for a very short Teams meeting

Webinars receive special handling, and this is where Microsoft Lists come into play. The connection between Teams and the content held in Lists is via the ThreadId property, a value which points to the Teams meeting space (the identifier is also used in the Teams webinar URL) used for the event. A thread ID looks like this:

19:meeting_MjE2Mjg0OGEtMGViMi00OGNhLTg3ODQtMWE3NjE2MDAzNzli@thread.v2

Exposing Teams Webinar Information for eDiscovery

To make the webinar information available for eDiscovery, Teams creates three lists per webinar in the in the meeting organizer’s OneDrive for Business account. This is the reason why Microsoft makes access to Microsoft Lists one of the prerequisites for organizing Teams webinars. Lists are only created for webinar events.

The lists for an individual event share a unique identifier (GUID) which Teams uses as a suffix to associate the lists for an individual event (for example, de93882234fb418fb3fd5ef7048026d4). The lists are:

  • Event: Stores event information such as its start and end time and webinar description and title. The ThreadId for the webinar is stored in this list. The webinar title and description can be edited in the list but the information created by Teams for the meeting cannot.
  • Questionnaire: Stores the attendance records for individual webinar attendees. The information about attendee details (like name and email address) can be edited in the list but information relating to the Teams meeting (like its URI) cannot.
  • Speakers: Stores details of the speakers such as their names and bios. This information can be edited in the list.

Updates made to list data are reindexed and available for search.

The webinar lists are hidden from the normal My Lists view shown to users when they open the Microsoft Lists app. To access the webinar information, go to OneDrive’s Site Settings and navigate to the Site Libraries and Lists page (Figure 3), where you can see the lists used by Teams along with other lists used by OneDrive like the site’s preservation hold library.

Lists for Teams webinars stored in OneDrive for Business
Figure 3: Lists for Teams webinars stored in OneDrive for Business

As an example, this is the URL for the site settings and list page for the KimAkers@office365itpros.com account.

https:// office365itpros-my.sharepoint.com/personal/kim_akers_office365itpros_com/_layouts/15/mcontent.aspx

If you choose to customize a list, you see the list settings, including its URL. For instance, the speaker list for an event has a URL like:

https:// office365itpros-my.sharepoint.com/personal/kim_akers_office365itpros_com/Lists/Speaker_de93882234fb418fb3fd5ef7048026d4/AllItems.aspx

Using the URL, we can open the chosen list in a browser. Figure 4 shows the speaker list for a Teams webinar.

Speaker information for a Teams webinar stored in a list
Figure 4: Speaker information for a Teams webinar stored in a list

Microsoft Search indexes the Information stored in OneDrive for Business. You can therefore search for someone’s involvement in a webinar by inputting their email address into SharePoint Search. The Digiform entries shown in Figure 5 are for the attendance rosters for two webinars.

SharePoint Search finds details of webinar attendance for a user
Figure 5: SharePoint Search finds details of webinar attendance for a user

Even better, the indexed information for the speaker, attendance, and event lists is available for eDiscovery. In Figure 6, we see some webinar items listed in a sample preview for a Core eDiscovery search. The items relate to speaker bios (highlighted in Figure 1), webinar description, and email addresses in the attendance report. Again, the Digiform entries found by the search point to lists stored in OneDrive for Business.

Core eDiscovery searches find webinar information
Figure 6: Core eDiscovery searches find webinar information

The Many Moving Parts of Microsoft 365

The way Microsoft 365 captures, stores, and indexes webinar attendance data is a good example of the Microsoft 365 substrate and ecosystem in action. Although many moving parts are involved, administrators and end users don’t see any of the complexity or connections involved. Some might be bothered by the ability of end users to update some webinar information stored in lists, but if you don’t tell them that the information is there, they might never discover where it’s stored.


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4 Replies to “How Teams Makes Webinar Information Available for Search and eDiscovery”

  1. Creating a Teams webinar creates a true mess of lists that the organizer will see on their office.com home page’s “recents” list. It causes confusion and support calls.

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