Hello,
Are the disappeared components from eCatalog or components with custom geometries?
The error suggests that the layout has been saved without “Include Components” option on. That means, component geometries from older versions of eCatalog models are not saved with the layout, and any imported CAD geometries are not saved with the layout.
It is recommended to save it always with “Include Components” on, if the layout is shared with anyone else.
To restore the layouts, please check the tutorial by keke:
How to migrate layout to new VC version - eCat Updates - Visual Components - The Simulation Community