If you retire a location attribute, and then go add a new location, the retired location attribute is still in the list of fields on the form. If you edit a location, the location attribute is still there, but you can't save the location because the location attribute isn't completed. The error is...
If data has been entered for a retired location attribute, it should be displayed (read-only). It should not prevent the location from being saved.
This happens with OpenMRS Version: 1.11.0 SNAPSHOT Build 403559.