Attach ics file

Is there a way to attach a calendar invite (.ics file) in the autoresponder email - so that event registrations can automatically have a calendar invite sent to the person signing up?

It is not possible to attach a calendar invite (.ics file) to the Autoresponder Email. However, you can upload a file to your google drive and just to add a link to your Autoresponder Email. This would allow your users to download it.