I can get outlook calender on my icloudcom address invites that appear on iphone and ipad but not in the MAc calender

If “Mac Calendar” means Outlook for Mac, add the iCloud account using Outlook’s dedicated iCloud/Microsoft Cloud option rather than as an IMAP account; if it means Apple’s Calendar app, first check iCloud.com to isolate the problem to that Mac.

If you use Outlook for Mac

Since account resets and ordinary synchronization have already failed, do not repeat them. Check how the account was added:

1. In Outlook for Mac, select Tools → Accounts.
2. Select + Add an Account.
3. Enter the @icloud.com address and select Continue.
4. Select Sign In to configure it through Microsoft Cloud.
5. If Outlook chooses another provider, select Not [provider]?, then select iCloud.
6. Complete authentication, open Calendar, and select the iCloud calendar in the navigation pane.

Current Outlook for Mac provides this direct iCloud-calendar synchronization path.^1^

Do not configure the address manually as IMAP: IMAP synchronizes email, not calendars.^2^

If you use Legacy Outlook for Mac

Legacy Outlook does not directly synchronize iCloud calendars through CalDAV. Use its documented subscription workaround:

1. Sign in to iCloud in a browser and open Calendar.
2. Next to the required calendar, select Share Calendar.
3. Enable Public Calendar, then select Copy Link.
   • Privacy warning: anyone who obtains this link can view that published calendar.
4. Sign in to Outlook on the web using the same Microsoft account configured in Outlook for Mac.
5. Open Calendar → Add calendar → From internet.
6. Paste the iCloud calendar link, assign a name, and select Save.
7. Confirm it appears under Other calendars.
8. Restart Outlook for Mac if it does not appear after several minutes.

This is a subscribed, view-only calendar rather than full two-way iCloud synchronization. The Microsoft account used in Outlook on the web must also be present in Outlook for Mac.^1^

If “Mac Calendar” means the Apple Calendar app

Perform one test before changing more accounts:

1. Open iCloud Calendar in a browser on the Mac.
2. Look for one of the missing invitations or accepted events.
3. Interpret the result:
   • Present on iCloud.com and on the iPhone/iPad: delivery to iCloud succeeded; the remaining problem is specific to the Mac’s Apple Calendar display or synchronization, not Outlook invitation delivery.
   • Invitation present but event absent: open the invitation and accept it, then verify which iCloud calendar receives it.
   • Absent from iCloud.com: check whether the event shown on the iPhone/iPad is actually under iCloud, Outlook, or another calendar. Apple devices can display calendars from several accounts together.^3^

The available Microsoft guidance does not document repair steps for Apple Calendar on macOS. If the event is present on iCloud.com but absent only in Apple Calendar on the Mac, continue through Apple’s Calendar/iCloud support rather than resetting Outlook again.

References

1. Outlook for Mac (#tab/outlook-for-mac)
2. How to sync calander in outlook to iphone outlook - Microsoft Q&A
3. Calendar has been wiped with iPhone update. Wondering if my calendar would be stored somewhere - Microsoft Q&A