2. Select Manage Workbook > Recover Unsaved Workbook . Excel file recovery options 3. From the list of files displayed, open the inaccessible file and save it. Solution 7: Open MS Excel in Safe Mode ...

Every now and then, when I try opening an Excel file, I get a message saying that "Excel cannot open the file 'file.xlsx' because the file format or the file extension is not valid.

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.

Greetings, I have a user who was working on an Excel 2007 file from a thumbdrive.. all of a suddem the file will not open and generates the following error: "Excel cannot open the file 'filename.xlsx' ...

Excel cannot open the 'test.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.

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 ...