Hi Mrs Konstantas,
Thanks for posting in our forum.
To help narrow down the issue, please try to start Outlook in safe mode (Press Win + R, type "outlook /safe", press Enter.) and see if Outlook can be opened properly.
It the problem continues, please try to repair Office via Control Panel and check the result:
Repair an Office application
It the issue still exists, please have a check in the Event Viewer when the problem occurs and see if anything useful would be recorded out there.
Best regards,
Yuki Sun
Please remember to mark the replies as answers if they helped.
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