Can't open XLSX file, extension not valid

Mathiasss 

If you have already tried common methods to repair a corrupted Excel file without success, and changing the file extension to XLS didn't work, you can try the following additional steps:

1. Open and Repair:

• Open Excel.
• Go to "File" > "Open."
• Navigate to the location of the corrupted XLSX file.
• Select the file, click on the arrow next to the "Open" button, and choose "Open and Repair."

2. Use Excel Viewer:

• Download and install the Microsoft Excel Viewer, which is a free application that allows you to view and print Excel files. Even if you can't edit the file, you might be able to view its contents.

3. Copy and Paste:

• Open a new Excel workbook.
• Try opening the corrupted file in Notepad.
• Copy the content from Notepad.
• Paste the content into the new Excel workbook.

4. Recover Previous Version:

• Right-click on the corrupted file.
• Select "Properties."
• Go to the "Previous Versions" tab.
• Check if there's a previous version of the file available and restore it.

5. Try on Another Computer:

• If possible, try opening the file on another computer with a different version of Excel.

6. Use Third-Party Tools:

• As a last resort, you might consider using reputable third-party file repair tools. Tools like Stellar Repair for Excel, as you mentioned, are designed for this purpose. Ensure you download such tools from trusted sources.

7. Check Event Viewer:

• Open the Event Viewer on your computer.
• Look for any error messages related to the Excel file. This might provide additional information on what's causing the issue.

8. Recover Data from External Hard Drive:

• If the file was originally on an external hard drive, try recovering it from the drive again and see if there were any issues during the transfer.

Remember to create a backup of the corrupted file before attempting any repair methods, especially if you decide to use third-party tools. If none of the above methods work, it might be worth reaching out to Microsoft Support for further assistance or considering professional data recovery services. The text/steps was revised with the AI.

 Hope this will help you.

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