Excel cannot open the file because the file formart or file extension is not valid.

Hello

I am really in need of urgent help to recover the data from my excel file. I did recently changed the job and copied my personal data to a hard drive. After losing my job, I tried to open the saved files from the Hard drive Many of the files are returning with an error. But, some are working. I really need help open an excel file which has personal data stored since last 6 years.
Please help me to resolve this issue. Appreciate your help.

Thanks
Venkat

I tried with changing to .xls.. But, unsuccessful

Hi Venkat,

This error occurs when you're using an unsupported Excel file format or the file is corrupt.

I have faced this error before, and "Open And Repair" fixed it for me:
1. Open your Excel Application
2. Click on File > Open
3. In the Open dialog box, select your faulty excel file (single click) and click on the drop-down arrow next to the Open button
4. Click on "Open and Repair."
Excel will ask you to repair or extract data from it.
5. Click Repair to retrieve maximum data.
If the repair option doesn't work, click on extract data (it will recover the data without formulas and values)

I hope this works out.

Best Regards.

copied my personal data to a hard drive

If this was from somewhere like One Drive, then it might be a syncing issue?