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What is your account type (POP/IMAP/Exchange)?
How do you share and add calendars? Please follow the steps in this article to reshare to check if there are any discrepancies: Share calendars in Outlook for Windows.
For the problem that shared calendars are not visible in Outlook. This can be due to a number of reasons, such as missing permissions, calendars being hidden, or syncing issues.
Here are a few steps you can try to fix the problem:
- Check Permissions: Ensure that the correct permissions are set for the shared calendar.
- Turn on Shared Calendar Improvements: In Outlook, go to File > Account Settings > Account Settings. Select your Microsoft Exchange account and choose Change. Then, go to More Settings, and under the Advanced tab, select the checkbox for "Turn on shared calendar improvements.
- Furthermore, for the calendar in Outlook, kindly try to use the tool Microsoft Support and Recovery Assistant to check if it is workable.
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