Clicking on the Investigate icon in the navigation bar opens the investigation view in the main window.
You may also get to this view directly from some dashboards by using table links.

For example, in the Service per Device dashboard, clicking a device name in the Services Successful Transaction widget
will load the Transactions widget under the Investigation view.

The investigation view is split into four sub-views:

Transactions

Raw Messages (for admins or users with appropriate permissions)

Extended Transactions

Payload Capture (for admins or users with appropriate permissions)