Autocad Exception - In Vl.crx Arx Command

Follow these steps in order from easiest to most advanced.

Follow these steps in order. Start with the simplest (no-risk) solutions before moving to more invasive fixes.

If you consistently see the "Access Violation Reading" error: autocad exception in vl.crx arx command

| Practice | Why it helps | |----------|---------------| | Keep LISP code modular | Isolate crashes to single files | | Avoid vlax-dump-object in production | Can cause memory leaks | | Always (vl-load-com) before VL functions | Ensures VL engine is ready | | Use (vl-catch-all-apply) in risky code | Prevents exceptions from crashing AutoCAD | | Update custom LISP for your AutoCAD version | Newer ARX APIs change | | Run (gc) (garbage collect) after heavy LISP | Reduces memory corruption |

AutoCAD stores user preferences, toolbar layouts, and palettes in the Windows Registry. If the registry keys associated with the current profile (Profile.aws) become bloated or corrupted, it can prevent the Visual LISP environment from initializing correctly. Follow these steps in order from easiest to most advanced

Use AutoCAD's "Reset Settings to Default" or launch with:

C:\Program Files\Autodesk\AutoCAD 20XX\acad.exe" /clean

Or hold Shift while launching → "Reset to default". Or hold Shift while launching → "Reset to default"

This determines if the issue is inherent to the AutoCAD install or caused by add-ons.

(vl-load-com)
(vl-string-search "a" "abc")

If this crashes, the issue is with vl.crx itself, not your code.