Why cannot I delete a phase

Not version-specific

Tekla Structures

Environment

Not environment-specific

Question:
We cannot delete some phases from this model. Some objects belong to these phases, but those objects neither appear in any list nor can they be deleted. How can we delete these phases?

Answer:
When you create a part two invisible points are created with it, one at the start and one at the end. The part and the points are created into the current phase.

When you move the part from one phase to another one, the points are not moved. Your phase may look empty, but there are invisible points in it. The invisible points cannot be deleted without deleting the part they belong to, but you can move them to another phase:

Select the phases you want to delete
Select Objects by phases (to select the invisible points in those phases)
Select another phase (that you don't want to delete)
Click Modify phase (to move the selected objects to the selected phase)

Those invisible points are moved from the old phases to the new phase, and now the old phases are empty and can be deleted.

When you delete a part, also the invisible points associated to it are deleted. None of the invisible points in your model are obsolete, each of them belongs to an existing part.