Hi @TravelAGoGo
In order to better solve your problem and perform more targeted tests, could you please tell me your outlook client version (File>Office account>About Outlook)? And I suggest that you can update Outlook client to the latest version.
The Outlook ribbon may keep on changing back to default due to app damage or corruption. Here are a few steps you can try to resolve this issue:
- Reset the Ribbon and then re-customizing it can help. Go to File > Options > Customize Ribbon and click on Reset > Reset all customizations.
- Repair Office: There might be an issue with your Office installation. You can try repairing it by going to Control Panel > Programs and Features, selecting Microsoft Office, and then clicking on Change > Repair. For instructions, see Repair an Office application.
- If the issue persists, we suggest that you create a new Outlook profile can sometimes resolve such issues. More information, see: Create an Outlook profile.
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