The administration and maintenance of Microsoft Exchange Server to ensure secure, reliable, and efficient email and collaboration services across an organization.
What's your Exchange server and CU version, or are you using Exchange online?
Yes, like the suggestion provided above, you could firstly re-configure your outlook profile, you could perform the operation in Control Panel as well
Verify the result again after finshing the operation, you could also check which mode are you using now, cached or online or offline?
If the issue still exist, you could consider using the SARA tool to help fix the issue:
Download here: Microsoft Support and Recovery Assistant
Introduction: About the Microsoft Support and Recovery Assistant
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