Fix Missing Scheduled Appointments In Microsoft 365 Calendars

Summary

This guide helps you troubleshoot and resolve: Fix Missing Scheduled Appointments In Microsoft 365 Calendars. Follow the steps below to fix the issue.

Common Causes

Missing appointments in Microsoft 365 calendars can cause significant disruption for NDIS and disability support providers who rely on shared scheduling for client bookings. When appointments vanish from shared calendars or fail to appear after migration, it is usually caused by incorrect delegate permissions, Outlook caching settings, or calendar publishing issues within Microsoft 365.

Quick Fix Steps

1. Check that the calendar owner has granted you the correct delegate permissions in Microsoft 365.
2. Verify Outlook caching settings if appointments are missing locally.
3. Confirm that calendar publishing is enabled for the shared resource.
4. Refresh the calendar view and check for synchronisation delays.

Detailed Instructions

Check Calendar Delegate Permissions

1. Open Microsoft Outlook on your desktop.
2. Right-click your calendar in the folder pane and select Properties.
3. Click the Permissions tab.
4. Locate the user who cannot see appointments in the list.
5. Select their name and review the Permission Level dropdown.
6. Ensure the level is set to at least Reviewer or Editor, depending on whether they need to create appointments.
7. Click OK to save changes.

Verify Outlook Caching Mode Settings

1. Open Outlook and click File in the top left corner.
2. Select Account Settings, then click Account Settings again from the dropdown.
3. Select your Microsoft 365 email account and click Change.
4. Look for the Use Cached Exchange Mode checkbox.
5. If appointments are missing locally, consider toggling this setting or switching to Online Mode to force a fresh synchronisation with the server.
6. Click Next, then Finish, and restart Outlook.

Confirm Calendar Publishing Status

1. Sign in to the Microsoft 365 admin centre at admin.microsoft.com.
2. Navigate to Users > Active users.
3. Select the calendar owner's account.
4. Check the Mail tab to confirm the mailbox is active and licensed.
5. Open Outlook on the web and go to the Calendar.
6. Right-click the shared calendar and select Sharing and permissions.
7. Verify that publishing is enabled and the correct access level is assigned.

Troubleshooting

Appointments Still Missing After Permission Changes

• Ask the calendar owner to send a new test appointment to verify permissions have propagated.
• Wait up to 30 minutes for permission changes to synchronise across Microsoft 365 services.
• Restart Outlook to force a refresh of folder permissions.

Shared Calendar Not Visible in Outlook

• In Outlook, go to File > Open & Export > Other User's Folder.
• Enter the calendar owner's email address and select Calendar from the folder type dropdown.
• Click OK to add the shared calendar to your folder pane.

Appointments Missing After Migration

• Check whether the appointments exist in Outlook on the web. If they appear there, the issue is local to the desktop client.
• Run the Microsoft Support and Recovery Assistant to diagnose synchronisation problems.
• Ensure the migrated mailbox has the correct legacyExchangeDN attributes to avoid delivery failures.

Still Having Issues?