How to resolve 'server responded with an error' on iMac Calendar using Monterey 12.7.6?

I keep getting the error message...server responded with an error...on my iMac Calendar. The three choices are revert to server, try again and ignore but none seems to do any good. What is wrong and how do I fix it? My iMac is late 2015 using Monterey 12.7.6 and it can't be upgraded to a newer OS.

[Re-Titled by Moderator]

Original Title: Repeated Calendar Error

iMac 21.5″, macOS 12.7

Posted on Jun 9, 2025 11:26 AM

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