Hi,
Please open a blank Workbook and check if you can open the problem Workbooks from File- Open.
If it works, this problem may related to the Windows 24H2 update, recently, some users have reported various problems with Office after Windows was updated to 24H2. This situation needs to wait for Microsoft to confirm and fix, it is recommended that you try to restore to the previous Windows version and check if the problem is fixed.
Then you can try to give a feedback to Microsoft about this problem:
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