Diagnosis
You are trying to delete an area type for which there are still entriesin the rental units.

System Response
The area type you selected is not deleted from the list.

Procedure
All area types which have entries in the building or in thecorresponding rental units are displayed in the area list. You can onlychange the entries for the building. If there is an entry in therental unit for the area type, it cannot be deleted from the list.Delete the area type in the rental unit where it is defined.