You can undo tasks in any order (provided that individual undo actions result in valid data). The undo operation sets the value of a resource to the value it had before the change to that resource.
In the case that the task that is being undone was one that created an object, there is no previous state to which an object can be returned-in other words, no object existed before this task was performed. Effectively, the undo operation deletes the new object from the session. In this case, errors occur for the objects that reference the one being deleted. You can view such errors on the View Conflicts page in the Change Center.
When you are not working in a session, you can access the View Configuration Changes page to see the sessions that were previously activated. You can undo these sessions. The system does not allow you to undo a session that was previously activated if an error in the run time configuration would result from the undo action. For example, if you attempt to undo a session activation that results in the removal of an object that is being referenced by another object, that undo action is disallowed.
It is possible to undo an undo action. In the Options column of the Undo of [task], click the Undo icon. ALSB supports unlimited undo. This means you can undo the undo that undid a previous undo, and so on.