Why is my curtain wall broken in Revit?

Answer 1

If nothing else is unusual about the wall (you aren't trying to create complex walls, force something that Revit isn't equipped to do, it may be a wall join problem. In plan view, from the Modify tab>Wall Joins, roll your mouse over the joint where the walls meet. A square box will appear, select the box, and on the green line, under the ribbon, it will give options to allow/disallow join, and join options. From there, Allow Join, then Miter. IF there is a wall join problem there, that will likely fix it.

Answer 2

Can you explain in more detail what exactly is broken about it? How are you trying to use it?