Hi @Cathy Sim
Welcome to our forum!
For better research, please provide more details about this case:
What is your account type (POP/IMAP/Exchange)?
What is the Outlook client version? Please make sure to update to the latest version.
What are the specific error messages?
Here are a few things you can try to sync your Outlook web calendar with your Outlook Windows calendar:
- Configure the email account as an Exchange account.
- Reset view settings: Sometimes, resetting view settings can help. Go to View > reset the view.
- Download and run the Microsoft Support and Recovery Assistant tool.
Also, based on my search, there is a related known issue here, which is currently being investigated by the official team, so please be patient and wait for the next update.
Thank you for your understanding and patience!
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