Runtime error for ModeltoOSM component - expected string, got NoneType

upon installing the LBT 1.3.0 on a network VDI, I receive the following fatal error when running thermal analysis.
Openstudio 3.2 and EnergyPlus 9.5 are correctly installed, as per the compatibility matrix.

Runtime error (TypeErrorException): expected string, got NoneType
line 37, in isfile, “C:\Program Files\Rhino 6\Plug-ins\IronPython\Lib\”
line 318, in prepare_idf_for_simulation, “C:\Users\a.botti\ladybug_tools\python\Lib\site-packages\honeybee_energy\”
line 624, in _run_idf_windows, “C:\Users\a.botti\ladybug_tools\python\Lib\site-packages\honeybee_energy\”
line 376, in run_idf, “C:\Users\a.botti\ladybug_tools\python\Lib\site-packages\honeybee_energy\”
line 237, in script

Any idea what the issue may be?


@andrea.botti ,

There is pretty clearly something wrong with the IronPython plugin for your Rhino installation and your problem doesn’t have anything to do with EnergyPlus or OpenStudio. What version of Rhino are you using (including the service release number)?

Maybe someone from the McNeel team might have an idea for what’s going on.

FYI, this is the line that is failing:

For some reason, we can’t check whether a file exists using the os module of your IronPython.

Hi Chris,
thanks for your reply. I am using Rhino 6, v6.35.21222.17001. The error shows on my personal laptop too.


Hey @andrea.botti ,

I took a closer look at your error message and realized that it’s not an issue with your Rhino IronPython and this is just a poor error message on my part. For some reason, your Honeybee model isn’t being translated into a valid OSM/IDF. Can you upload a minimal sample file that is needed to recreate the issue?

FYI, I added a fix that will make the component error message much clearer for this case:

Sorry again for my original misdiagnosis of the problem. If you manage to get a file that recreates the issue, I’ll investigate.