If you see something like this:
[Arnold]: MAXtoA_Shaders.dll was compiled against non-compatible Arnold 18.104.22.168
it usually means you have an older Arnold trying to load something compiled with a newer Arnold. There’s two common reasons for this happening:
- The system PATH includes the location of the older Arnold, so the older Arnold is loaded instead of the Arnold version included with the plugin.
- The plugin install is messed up, and has the wrong Arnold version in it.