Hi Wenkai,
To
narrow down the issue, I want to confirm the following information:
#1.
What is the type of email account you have setup in Outlook? For example POP3, IMAP, Exchange Active Sync (EAS) or Microsoft Exchange.
To check the type of email account configured in Outlook click on File > Info>Account Settings > Account Settings drop-down. EAS account refers to Hotmail.com, Outlook.com or Live.com email accounts.
#2. I suggest you try to repair Office from Control Panel then see the results
(Please back up the data in case), here is the reference:https://support.office.com/en-US/Article/Repair-an-Office-application-7821d4b6-7c1d-4205-aa0e-a6b40c5bb88b
(select Quick Repair)
#3.
There is a possibility that some Add-in is causing the problem. To rule this out, start Outlook in safe mode. Hold CTRL key and click on Outlook icon. Don't leave CTRL key,
till it asks for the confirmation about safe mode.
#4.
please provide the Outlook version to us for us to check further.
Go File >
Office Account > entire screenshot of Product Information. (remove the PII please)
We truly appreciate your kind cooperation.
Thanks,
Linda