Hi,
Does this error continue if we try starting Outlook in safe mode? Press Win+R to open the Run command, type
outlook /safe and press Enter.
You may also consider to recreate the OST file to see whether it helps. To do this, exit Outlook, find the OST file, rename it by appending .old to it. Then restart Outlook, a new OST file will be synced from the server.
If above doesn't help, also try with a new Outlook mail profile. For your convenience: Create an Outlook profile.
Regards,
Steve Fan
Please remember to mark the replies as answers if they helped. If you have feedback for TechNet Subscriber Support, contact
tnsf@microsoft.com.

Click
here to learn more. Visit the dedicated
forum to share, explore and talk to experts about Microsoft Teams.