Aloha.

So, even this MWE, the export to *.ics does not work as expected. The 
test.ics file has no events when

M-x org-icalendar-export-to-ics

is invoked.
=========================  Contents of test.org listed below 
=================
-*- org-icalendar-use-deadline: (todo-due);  -*-
MY PROJECT -*- mode: org -*-
#-*- mode: org -*-
#+STARTUP: showall

* Welcome to Org mode

   Welcome, and thanks for trying out Org mode. Making outlines in
   Org is very simple. It is just text! Just start typing.
* This is a headline, it starts with one or more stars
   A heading has one star, a sub-heading two, etc.
* Working with lists
** Moving around in our outline
** TODO Moving around headline
** TODO This is an event with a Deadline
DEADLINE: <2024-06-20 Thu -30d>
=========================  Contents of test.org listed above 
=================

Any advice would be appreciated.
J.


On 6/8/24 10:38, Ihor Radchenko wrote:
> John Helly<hellyj@ucsd.edu>  writes:
>
>> I modified the variable specification to be:
>>
>> -*- org-icalendar-use-deadline: event-if-not-todo;  -*-
>> and get the following error:
>>
>> 'Wrong type argument: listp, event-if-not-todo'
> That's because the value should be a list.
>
> -*- org-icalendar-use-deadline: (event-if-not-todo);  -*-
>

-- 
John Helly / San Diego Supercomputer Center / Scripps Institution of Oceanography
https://www.sdsc.edu/~hellyj  / 808 205 9882 / 760 8408660