If you see any error message similar to the following, the synchronization is not working properly. Remember, the repair process may take some time, especially for accounts with large amounts of data. Check with your email provider for instructions about how to create an app password for your email account. If you're using an Outlook.com, Microsoft 365, or Exchange account, you won't have advanced mailbox settings unless the account was set up using advanced setup. We're sorry you're having problems with the Mail and Calendar apps for Windows 10. To fix the issue, please try each of the following solutions in order.

The reason is that if the Calendar that is not syncing is not an Outlook calendar, it takes up to 24 hours for events to be reflected in Outlook. If you have less than 5GB of free storage, please make sure to delete unnecessary data, images, videos, or apps you no longer use. Even though this is not common as iPhones and iPads generally have lots of memory, if you’re running low on storage, chances are that new events won’t show up in your calendar. Regardless of the type of calendar provider you’ve connected to Google Calendar (Outlook, iCloud, or another Google Calendar), the first step is to remove it from Google Calendar. To do so, follow the same steps as the "Manually sync Google Calendar to Outlook" section above.

Additional troubleshooting tips for ‘why won’t my Outlook calendar sync?’

If you’re using an IMAP or POP account, some of these options may not be available, and you might need to check your account-specific sync settings. It’s worth noting that sometimes, what appears to be a sync issue might actually be a delay. Outlook doesn’t always sync instantaneously, and there can be a short lag between changes made and their appearance across all devices. The most common cause of an out-of-date account is an incorrect password. If your password is incorrect, you'll see a message asking you to update your password. If you still can't sync your email after removing your account and adding it again, you might need to add the account using advanced setup.

• Network hiccups or server problems can also disrupt the smooth flow of calendar data, leading to inconsistencies across different users’ views.
• Using a Calendar Sync Tool you won’t have to troubleshoot why your Google Calendar is not syncing with Outlook, or manually sync them.
• Try the general troubleshooting solutions in Troubleshooting Mail and Calendar apps for Windows 10.
• Regardless of the type of calendar provider you’ve connected to Google Calendar (Outlook, iCloud, or another Google Calendar), the first step is to remove it from Google Calendar.
• Calendar syncing plays a pivotal role in maintaining an organized and efficient schedule.
• Shared calendar syncing issues with Outlook can lead to overlooked appointments, missed team meetings or scheduled calls with customers or clients.

Why has my calendar stopped syncing?

Shared calendars in Outlook are a powerful tool for team collaboration, but they can sometimes encounter sync issues. Understanding why these problems occur is the first step in resolving them. Remember, recreating your profile is often a last resort when other troubleshooting steps Additional Info have failed. It can be time-consuming but is sometimes necessary to resolve persistent issues. Even though Outlook is one of the most used calendar apps among individuals and businesses, offering plenty of features, sometimes it stops syncing.

Additional resources

Always ensure you have a backup of your data before making significant changes to your email configuration. Remember to restart your device after installing updates to ensure all changes take effect. If there's a feature you think is missing from the Mail and Calendar apps, or if a feature in isn't working properly, you can provide feedback directly to the Mail and Calendar team. If your password isn't the problem, you might have a certificate error.

Solutions to Fix the Shared Calendar not Syncing issue with Outlook

Using a Calendar Sync Tool you won’t have to troubleshoot why your Google Calendar is not syncing with Outlook, or manually sync them. If you’ve shared a Google Calendar with an Outlook Calendar, updates in Google Calendar take up to 24 hours to reflect in Outlook Calendar. If none of the above steps work, you may need to troubleshoot further or seek additional support from Microsoft or a qualified IT professional. My theory is that there may be some work stations that have a long uptime and as a result finding it difficult to resolve sync services. We’d (IT Support) had a play around ourselves, and it doesn’t seem to be a web app or desktop app issue. If you don't see a calendar option or your account was listed as IMAP, tap More and select Remove account.

How to fix Outlook Calendar sync issues on iPhone or iPad

By following these steps, you should be able to resolve most Outlook calendar sync issues, whether on desktop or mobile devices. If problems persist, consider reaching out to Microsoft Support or your organization’s IT department for more advanced troubleshooting. This article is part of our comprehensive series on synchronization issues, designed to help you navigate the sometimes tricky waters of digital calendar management. Here, we’ll focus specifically on troubleshooting Outlook calendar sync problems, exploring common causes and providing quick, effective solutions to get your schedule back on track. Below are the common reasons behind the shared calendar synchronization issues. Remember, patience is key when dealing with shared calendar sync issues.

Solution 6: Clear Offline Items and Verify Calendar Sharing Settings

First, ensure you have the necessary permissions to view and edit the calendar in question. Check your send/receive settings to make sure Outlook is set to update frequently enough. Verify that you’re not in offline mode and that your internet connection is stable. If you’re using a shared calendar, ask the owner to re-share it with you, as sometimes permissions can become corrupted.