Few things are more frustrating for a designer, engineer, or architect than being deep in a complex drawing session only to have AutoCAD crash without warning. Among the most cryptic and persistent of these crashes is the (or similar variations involving acismobj20.dbx ).
Think of it as a "check engine" light for your model’s geometry. By learning to identify, isolate, and repair corrupt ACIS objects, you can turn this career-stopping crash into a minor, five-minute inconvenience.
Typically found in:
This is the nuclear option.
Does AutoCAD crash when opening any file, or just one specific file? autocad fatal error acismobj20.dbx
If the error occurs when opening a specific file, the drawing itself is likely the culprit.
Somewhere in your drawing is a "sick" solid—an object with non-manifold geometry, zero-thickness faces, or internal topological errors. When AutoCAD’s ACIS engine tries to read, save, or render this object, it divides by zero (metaphorically) and dies. Few things are more frustrating for a designer,
Have you encountered the acismobj20.dbx error? Share your horror story (and solution) in the comments.
Users frequently report the crash occurs when clicking from Model Space into a Layout (Paper Space) containing a corrupt viewport. The viewport tries to generate a hidden-line removal or shaded view of a bad 3D object, and the engine fails. By learning to identify, isolate, and repair corrupt