There could be several reasons why Excel is unable to open your file.
Some common solutions include unchecking the Ignore DDE box, turning off add-ins, repairing Microsoft Office, resetting Excel file associations, disabling hardware graphics acceleration or reaching out to Microsoft Support.
Another solution is to try repairing the workbook manually by clicking on the File tab, then Open.
In the Open dialog box, select the corrupted workbook that you want to open.
Click the arrow next to the Open button, and then click Open and Repair.
You can then choose to either recover as much of the workbook data as possible by clicking Repair or extract values and formulas from the workbook when an attempt to repair the workbook is not successful by clicking Extract Data.
If I may recommend, add more information about your digital environment to your topic/concern/problem. This would help anyone who would like to help to have a better picture of the topic/issue/problem, so you could also get a more accurate and faster solution suggestion.