Calendar Subscription (Public iCloud) Error

I have subscribed to several calendars for sports teams via iCalShare.com. It's literally been years with no issues. As with you, they all stopped working on my MacBook Pro when I upgraded to Ventura. Also like you, they still work fine on my iPhone and iPad. Clearly a bug (or hidden "feature") in Ventura. I've tried deleting them all and reinstalling, but nothing helps.

Oddly enough, I also get the same issue with the built-in Holidays calendar that is available when going into Calendar preferences and selecting "Show Holidays Calendar". I get the following error:

Your subscribed calendar “US Holidays” couldn’t be refreshed. There was an unexpected error with the request (domain SubCalICSDataActorErrorDomain / error 3).

FWIW, the error message is a little different when it's one of the subscribed sports calendars. The error I reported above was from the Holidays calendar available from Apple. This is what I get from the iCalShare (sports team) calendar subscriptions:

Your subscribed calendar “Florida State Seminoles Calendar (ncaaf)” couldn’t be refreshed.

There was an unexpected error with the request to refresh the subscribed calendar “Atlanta Falcons Calendar (nfl)” (error 3).

Definitely agree this should be filed as a bug with Ventura. Thanks!

I don't think so. That looks like a different issue. The calendars I am subscribed to are iCal calendars, not Outlook. Ironically, mail is working faster and better than ever for me with this latest release. I used to have issues with mail loading and displaying in the native mail application (from a Gmail account). It would download the headers, but it might take minutes for the content to display. It was so slow sometimes that I just opened up mail in a browser and even then, changes in the browser such as reading or deleting mail wouldn't show up in the Mail application until much later. My wife had the same problem on her iMac with different accounts and we both experienced it on our iPhones. With Ventura, mail has been loading and updating pretty much instantly across all of our devices now.

Also, I do have an Exchange account too, which I sync with my Calendar and Tasks. To keep the (work) mail separate though, I use the Outlook app for mail. It's worked flawlessly for me with Ventura, again, better than it did prior to the upgrade. As I've told several friends and family members, this is the first upgrade that I can recall where everything has run significantly faster than before. That's true on my one year old MacBook Pro with an M1 chip and with my wife's five year old iMac with an Intel chip. I've been pleasantly surprised by the speed and performance improvements.

True. In any event, it sounds like there are enough issues with calendar syncing that, hopefully, it will get some attention in an upcoming patch…