Lotus Notes iCal Feed
When trying to open my Todoist calendar entry in Lotus Notes I received the following error: "Notes cannot import your file at this time. Your file is not supported." I can see the entries on my calendar, just not open them.
Here is what I found about this issue from IBM support:
iCalendar Version 1.0 .ics files are not supported for import into Notes 8. Attempting to import them will generate the following error:
"Notes cannot import your file at this time. Your iCalendar File is not supported."
It seems like iCal URL's that end with .ics (like Google Calendar) seem to open fine when subscribed through Lotus Notes.