Calendar can’t read this imported calendar file

I have the exact same problem after reinstalling macOS 11.6.6 Big Sur. If I right-click on the .ics file and choose Open With and then choose Calendar (instead of CalendarFileHandler), it imports the event without issue. However it is a pain in the *** to have to do this every.single.time. I want to import an event. I've never had this issue before, so it seems likely that it is a flaw in the 11.6.6 update.

Same problem, same OS 11.6.6. Solution!! If I drag the .ics file to my hard drive (i.e. Desktop) and right-click, open with... Calendar then it works! Terrible workaround, but better than not working or having to rely on Google (gasp.)

Another workaround: I found that if I open the .ics file with Calendar instead of CalendarFileHandler, the event imports.

FYI - I'm thrilled to report that after updating my Macbook Pro from to Big Sur 11.6.6 to 11.6.7 yesterday, the calendar functionality works like it used to!!

Hi, shtark1,

Make sure you are following the steps outlined in Import or export calendars on Mac - Apple Support to import your calendars.

If so and the issue continues, try importing them while booted in safe mode, then a new user account. These steps will allow us to isolate the issue from something occurring specifically in your user account, to something occurring across the system.

You can get information on booting into safe mode, what it does and why we use it to troubleshoot, and how to proceed with your findings here: How to use safe mode on your Mac - Apple Support

For information on creating a new user account, check the steps here: Set up users, guests, and groups on Mac - Apple Support

If you still need help after that, please get in touch with Apple Support directly. You can do that here: Get Support.

Thanks for visiting the Apple Support Communities.

Have a great weekend.

As a workaround to the error you're shared appearing when double-clicking on the .ics file, I found that I can import the event: File --> Import from Calendar and select the .ics file. Maybe that will work.

I am receiving the same error message when clicking on ADD TO CALENDAR on a webpage. I can confirm this functionality definitely quit working after updating to Big Sur 11.6.6 - the update to 11.6.6 appears to me to be the problem. I do not have a problem if I perform the same functionality on my iPhone 13 Pro Max running iOS 15.5.

When my computer updated to 11.6.6 this and other annoying problems began. Cannot click on calendar files, cannot open PDFs from email, cannot give email permission to open documents, etc..

Hopefully when I have time for the next update this goes away, but I can say it was 100% because of updating to 11.6.6

This worked for me! I haven't installed any updates or anything in my computer and I have been getting the same error. This solution, opening the ics file through Finder, worked for me. Thank you!

I have had the exact same problem after applying macOS 11.6.6 (to 11.6.5). I reinstalled macOS, the problem went away, and now after a few days it's back.

That didn't work for me. Any other solutions?

This worked for me. Thank you!

Same problem :( and how to fix it?

NO!