Hi anonymous user
Welcome to Q&A forum ~
> even uninstalled and reinstalled Office 365.
Did you install Office from Office 365 portal?
Or did you run ODT with configuration file (.xml)? If so, please share us with this configuration file.
Does this issue occur with other Office apps? Such as Word, PowerPoint.
If you press Alt + F11, will the VBA Editor shown up?
If you can see the VBA Editor, please check whether there is any macro running.
I would suggest you right-click Excel, run as administrator to check this issue.
Then it's recommended to run Excel in safe mode to check these button.
Safe mode could help us troubleshoot installed COM add-ins.
Besides, you could temporarily disable antivirus software.
Any updates, please feel free to post back.
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