Hi Matthew,
I would suggest trying a few solutions that might help resolve the issue:
Firstly, you can try performing clean re-install of support package then try building model again. Here is a link to a guide on how to perform a clean re-install of a support package:
Additionally, it might be possible that your model has some settings or configuration parameters that are causing this error. You can try to create new blank model and copy paste the content of old model into the new model and then try reconfiguring the new model after that you can try building this new model.
Another possible issue could be that you are trying to include header file which has spaces in its path. You can remove those spaces and try building model again.
Below, I have attached link to a MATLAB Answers thread that discusses an issue similar to yours :
Hope this helps.
