Getting error "excel can not open the file xlsx because the file format or extension is not valid"

Hi,

Based on the error message you provided, this file may have been saved as an Excel binary workbook. However, the workbook has an .xlsx extension that is appended to the file.

Try to change the file name from ".xlsx" to ".xlsb" or ".xls" to check the result.

One other possible cause is the file is corrupted, open Excel and click File -> Open -> Browse to the file location, select the file, and choose "Open and Repair", check if this helps in this scenario:

Regards,

Melon Chen
TechNet Community Su