Hi everyone,
I’ve been running into a recurring issue with Grasshopper in Rhino 8 and couldn’t solve it.
Issue
When I open any Rhino file by double-clicking the .3dm file in Windows Explorer, Grasshopper fails to load and shows the following error:
Error occurred loading plug-in
The type initializer for ‘Grasshopper.GUI.Canvas.GH_Canvas’ threw an exception.
Observed behaviour
1. .NET Framework runtime
-
If I double-click a .3dm file: Rhino opens the file normally, but launching Grasshopper triggers the above error.
-
If I open Rhino first, then open the same .3dm file from inside Rhino: Grasshopper loads perfectly, no error.
2. .NET Core runtime
- The problem disappears entirely. Grasshopper loads correctly even when double-clicking the .3dm file.
Additional context
The problem started recently after I installed the Butterfly plug-in. I’m not sure if it’s related. I’m currently unable to uninstall Butterfly to confirm. The issue did not occur previously when I only had Ladybug, Honeybee, and Radiance installed.
I found this related thread, but it doesn’t describe the same scenario, nor it received any responses:
GH under .NET Framework not loading in Rhino 8 — GH_Canvas exception
Has anyone else experienced this or found a way to prevent the GH_Canvas initialization error when using the .NET Framework runtime?
Thanks in advance for any insights!
Setup
Running Rhino 8.24.25281, Windows 11.
I have uploaded Rhino System Information file
Rhino System Information.txt (3.3 KB)