The reason for renaming, as you have probably already guessed, is to '.leave yourself a trail of breadcrumbs.' in case you get lost in the woods, metaphorically speaking. PAT files when the Hatch command is invoked so you don't want it looking for too many files with a. KT277: Maybe rename acad.pat to acad.pqt so AutoCad doesn't try to reference it? AutoCad is written to look for.