Dear Seniors,
I have one .xlsx file which shows an error "Excel cannot open the file 'file name.xlsx' because the file format or file extension is not valid. Verify that the file has not been corrupted and that the file extension matches the format of the file."

The said file had a data since 2013 very difficult for me again organise the data can any body help / guide for the recovery of the excel file.
Regards,
Kosh
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