Hi @AJ ,
Did this problem happen suddenly recently? Have you performed any special operations?
To avoid conflicts brought by add-ins, try running Outlook Safe Mode: Press Windows key +R, type outlook /safe in running command. If Outlook safe mode works, disable the add-ins following steps mentioned below and determine the problem causing add-in:
- Click on File menu, click Options, Add-ins, Go button besides Manage: Com-in Add.
- Check if there are add-ins listed, clear the checkbox.
- Close the Office program and restart it.
- Disable each add-in one at a time, restart the Outlook, and repeat the above procedure.
Corrupted profiles can also cause problems, create a new profile to see if the problem reproduces: Go to Control Pane > Mail > Show Profiles > Add, then add your account.
If above doesn't help, try repairing Outlook
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