I prefer desktop clients to web interfaces. I can CMD-tab between apps running on my computer far faster than I can switch to my web browser and then have to hunt through the open tabs to find my mail or calendar. (Yes, I know I can pin tabs. That’s another issue for another day.)
My employer uses Microsoft 365 for email and calendars, etc. Apple’s Calendar app uses Exchange Web Services (EWS) for synchronization. M365 uses a more modern sync stack, Graph + MAPI. The mismatch between these two methods can, and does, break synchronization between the Apple Calendar app and the M365 calendar it is showing. These breaks occur silently.
There are three background processes involved in synchronization for Mail and Calendar:
By quitting Mail.app and Calendar.app and then killing those processes, sometimes the synchronization will catch up.
sudo pkill exhangesyncd
sudo pkill CalendarAgent
sudo pkill accountsdWhen this fails to correct the issue, there are more steps that can be tried.
You can clear the Exchange Calendar cache. This does not wipe out the calendars, it only resets the Exchange EWS state.
rm -rf ~/Library/Calendars/Exchange*
rm -rf ~/Library/Calendars/Calendar\ Cache*
rm -rf ~/Library/Calendars/com.apple.CalendarAgent/Data/Library/CalendarAgentThis should force a re-pull from M365. Reopen Calendar and give it time to synchronize.
The big-hammer solution, if the above steps fail, is to reboot the computer. Not ideal, but it (usually) works.
I can either switch to using the web interface or use Microsoft Outlook. As I said at the top, using web interfaces is not my thing. Switching to Outlook is a reasonable solution, but one I struggle with as the UI is clunky to my way of thinking.
For example: In the “new” Outlook, you can only have a multi-line (sender / subject / preview) view in the Inbox if you have the message reading pane enabled. If you want to hide the message until you are ready to open it, and therefore you disable the reading pane, you are forced to have a single line entry for each message in the Inbox.
The legacy Outlook does allow 1, 2, or 3 line previews with no reading pane, but Copilot isn’t available with the legacy Outlook.
I know I’m being stubborn and picky about the tools I use, and how I want to configure those tools. Not terribly surprising as my career in IT has been built on paying attention to minute details. The “how it looks” is as important as the “what it does”.
I’ll install and configure Outlook and give it a try, while searching for a solution to the synchronization issue between M365 and Calendar.app.