Whether the problem is an invalid Excel file format or extension or an Excel file that cannot be opened due to corruption, rest assured, there is a solution for your situation.

1. Change the Extension Manually When the file extension doesn’t match the format, changing it manually helps Excel read the file correctly. Adjusting the extension (e.g., from .txt to .xlsx) aligns ...

To fix the Excel file format does not match extension error, trying opening the spreadsheet with the Open and Repair option or changing its file extension.

If you cannot open an Excel file and see Excel cannot open the file because the file format or extension is not valid error, see this post.

With the Excel extension is not valid error, try starting the app in Safe Mode, repair the workbook or open the file in another program.

Locate the file in File Explorer. Click on the View tab at the top and check the File name extensions box. You should now see the .xlsx, .xls, or a similar extension at the end of your Excel file.

A better alternative is to use an Excel file repair tool that helps fix common Excel file corruption errors and recover data in minimum possible time. But before we discuss the solution, let’s first ...

The Excel file repeatedly closes Methods to Repair Corrupted Excel Files When Excel detects a corrupted file, it automatically starts the file recovery mode and tries to repair the file.

If your Excel files are opening in Notepad on Windows PC, here's how you can reset the settings to make .xls, .xlsx, etc files open in Excel.

Your Excel file is corrupted but the Open and Repair function (opening and repairing) does not work. Follow the instructions below to recover your data!