Hi @Trond Gunnar Raa ,
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What's the version of your Outlook? (File > Office Account > About Outlook). Please make sure you have upgraded your Outlook to the latest version.
Based on the above, it's suggested that you could try to use the Microsoft Support and Recovery Assistant, which works by running tests to figure out what's wrong and offers the best solution for the identified problem.
If the issue persists, please try the following steps:
- Try the solution as Reza-Ameri mentioned. If this is still the issue in safe mode, it is suggested that you could try to create a new profile(Control Panel>Mail>Show Profiles>add) and add the account for testing to check if there are some differences.
- If the above doesn't help, considering that it would also be affected when the outlook program itself is damaged, it is recommended that you try to fix the Office application.
- Considering the impact of some third-party programs on your computer, please try to perform a clean boot for windows and check if the issue still occurs.
Hope to help you!
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