Profile families are loadable (component) families but they don’t exist on their own in projects. They are either used to create solid and void forms in the family editor, in-place families in projects or applied to System Families in projects. For example, a Railing, Sweep, Reveal and Floor Slab Edge can all use a Profile family.
Occasionally I’ll get a generic sort of warning regarding the system family I’m trying to make, telling me “Sorry Steve, I can’t make this thing for you”.
Quite often the reason Revit is complaining is because I was sloppy making the Profile family. You may recall I’ve written about good sketches and bad sketches in the past.
Regardless the error message could certainly be written better; to mention that such an error may be related to a profile that isn’t created properly. At this time, the error trapping process may not be able to reach deeply enough into the sketch mode process, for example like we use to create a Floor Slab Edge. Regardless, there is no reason the error message couldn’t mention a common culprit, something to prod us to look more deeply for…