arKItect uses a fast Excel generation method that require a lot of memory. If the export you are trying to make is too large (more than 10 000 lines on an Excel sheet), it might not be able to finish.
A warning appears if that specific case appears :
There is 2 possibilities to avoid that:
You should always restart your arKItect tool after the error described above to avoid any further issues with the tool.
This method use your local excel to work, you are required to close all Excel/VBA windows before using it. It is also slower than the fast method implemented in arKItect 4.1.0.
This setup is not saved, it must be activated manually at each arKItect session.
To activate this method go into Tools -> Script -> Excel -> Disable XLSX mode and right-click on it.
You can now launch your Export again with the same setup.