Hi @Cristian Angheluta ,
I suggest you try to check if the Administrator profile can work without problem in Excel/PowerPoint.
Try to re-install DirectX.
You can also collect the event log and provide us with the whole error messages of event log.
Steps of collecting event log:
Open Event Viewer to check whether there's any error about the Excel/Word crash issue.
Press Win + R, type "eventvwr" in the blank box, press Enter. In the Event Viewer, browse to Windows Logs -> Application, there may be some errors after the crash.
Please try to collect this event log and post the whole event log message here. I can get more information about your issue from this message and help you solve it.
If the response is helpful, please click "Accept Answer" and upvote it.
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