Hello,
when I try to load RhinoInside.Civil3D I get following error.
thanks for any kind of advice how to proceed to start RhinoInside.Civil3D.
Best
Ondřej
What versions are you running? (Civil, Rhino, Rhino.inside.Civil3d)
Civil 25
Rhino 8 (8.27.26019.16021, 2026-01-19)
Rhino.inside.Civil3D => Downloaded week ago.
A couple of things you could try, update Rhino to the latest, and make sure you are using the latest
Rhino.Inside.Civil3D (Currently 1.2.29).
But I suspect this is a dll conflict with another plugin, the message says it found the dll, but refused to load it, typically this is because as another application/plugin has already loaded another version of that dll.
Just double check the dll exists here:
%AppData%\Autodesk\ApplicationPlugins\Rhino.Inside.AutoCAD.bundle\1.2.29\Win64\NET8
Look for the CommunityToolkit.Mvvm.dll typically its the first item when sorted by name, it’s right click properties should be identical to this:
Are you able to list what other plugins you have installed for Civil3d?
I have lates Rhino.Inside.Civil3D version (1.3.1). Rhino says “Up to date”.
CommunityToolkit.Mvvm.dll says same as your image. Plugin is installed into slightly different path. Error stays the same. 
I am not able to list all plugins. We have some installed together with ACAD and I develop some plugins as well. However, I don’t think this .dll is used in my plugins.
Best
O.
If the file details match the screenshot and you’re still getting the same error, then another AutoCAD plugin is loading a different version of that DLL before Rhino.Inside gets to it. Whichever one loads first wins, and ours then gets refused.
I can look at resolving this specific DLL, but without knowing what else is on your machine it’s hard for me to reproduce the error. It’s also could be the first of several. Both plugins are loading into the same process and the same load context, so any assembly with different versions we both ship is a potential clash: resolving this one may just move the error to the next name down the list - where as if we know the other plugin we can make sure to fix them all.
If you cannot list the other plugins you have installed for Civil 3D, then the quickest way to identify the culprit is Process Explorer: start Civil 3D, then in Process Explorer select acad.exe, press Ctrl+D for the lower DLL pane, and find CommunityToolkit.Mvvm.dll. The path it’s loaded from will tell us which plugin is winning the race.
