creating solid geometry from stl files

Hello everyone,

I'm newbie in Inspire.

When i imported the stl file into inspire, i couldn't analysis. After reading an answer of a similar question in our forum, i figured it out that i have to create solid geom from stl file.
But the question is how do i know if the solid model can be created automatically from stl file, or i have to do it on my own.

Thanks.