The ActivityOpen action is a System Action that explicitly forces a Human Activity instance to be opened in an end-user's Taskbox. Normally, this System action is used to automatically open the next Human Activity task for the end-user when the NextHumanActivityId output parameter is not empty after:

Although this System action opens a Human Activity task in the Taskbox, it does not automatically navigate to the web screen as would happen if the end-user opened the task in the Taskbox. For that to happen, use the HandlingURL output parameter together with the External Site tool in the action flow.

Input parameters

ActivityId: Id of the activity instance.

Activity Identifier Type. Mandatory.

Output parameters

HandlingURL: the URL of the web screen that is set as the Destination for the given process activity instance.

All of the existing arguments in the URL are resolved, so that the returned URL has the correct argument values.

Text Type.


The On Open activity callback action is executed.

The On Open activity callback action is invoked using a different transaction and session from the transaction and session used when invoking the ActivityOpen. Only the Session.UserId is transported.

See Also

About Processes | Process Activities Life Cycle | Process Activities Callback Actions | Overview of System Actions and Functions