If I load (enable) the houdiniEngine plug-in (houdiniEngine.mll) either by turning it on in the Plugin Manager window or by code
cmds.loadPlugin('houdiniEngine')
// Error: file: C:/Program Files/Autodesk/Maya2022/scripts/others/pluginWin.mel line 316: Unable to dynamically load : C:/Program Files/Autodesk/Arnold/maya2022/plug-ins/mtoa.mll
//
// Error: file: C:/Program Files/Autodesk/Maya2022/scripts/others/pluginWin.mel line 316: (mtoa) //
However, if I close and restart Maya the Arnold plug-in always starts fine every time, so long as I haven't started HoudiniEngine.mll. I've seen plenty of plug-ins not start due to missing dependencies and such, but never seen this kind of behaviour where plug-ins are clashing with, or impairing, each other.
If I start Arnold first and then HoudiniEngine it seems to work, but a) I'm not sure that's enough to convince me everything is fine there, and b) I really don't want to have to enforce Arnold to be enabled by default on startup for every user in the studio as a workaround.
Has anyone got any ideas what's happening here, or does anyone know of some way to debug the plug-in initialisation to diagnose what's clashing?