Excel cannot open the file because the file format or file extension is not valid verify that the

A common error message that usually occurs when someone tries to open an Excel file in Windows is Excel cannot open the file because the file format or extension is not valid. Make sure the file is not corrupted and that the file extension matches its format. This error message is encountered especially when the file is either not compatible with the Excel version or it is corrupted. Let’s try to fix this issue.

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Sometimes, this error could be due to incompatible or unsupported file formats. Versions of Excel since 2007 use Office Open XML as the primary file format but are backward-compatible with the earlier versions of Excel files. A glance at the file extension will tell you straight away whether the program can open that file.

If the file you’re attempting to open is in one of these formats, it won’t open because it’s been corrupted. That’s because the file extension is compatible with Excel:

Excel Workbook. xlsx

Excel Macro-enabled Workbook. xlsm

Excel Binary Workbook. xlsb

Excel Macro-enabled Template. xltm

Excel Add-in. xlam

Spreadsheet. xls

Excel Template. xlt

Excel Macro. xlm

In addition, documents in these non-Excel file extensions can be opened by the program, though functionality might be reduced in some fashion:

XML. Spreadsheet 2003 or XML formatted files. xml

Lotus Spreadsheets. prn

Tab delimited/Unicode text files. txt

Comma-separated values files. csv

Data Interchange Format files. dif

Symbolic Link Format text files. slk

dBase Data Files. dbf

OpenOffice Files. ods

XML Paper Specification Files. xps

Portable Document Format files. pdf

Note that this isn’t an exhaustive list. Excel can open files with other extensions, including html.

How to Fix the “Excel Cannot Open the File Because the File Format or File Extension Is not Valid” Issue on Windows 10

Sometimes, when opening a file in Excel, the program displays this error message instead:

Microsoft Excel

Excel cannot open the file [File Name] 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.

If you encounter this error in any version of Excel since Excel 2007, three options are open to you:

1. Check the file extension and change it if needed.
2. Repair the file with Excel’s inbuilt repair tool.
3. Change group permissions for the file.

Let’s explain each option in more detail.

Solution 1. Check the File Extension

If you’re unable to open the file, it could be due to an unsupported file extension. To be frank, this is very rare nowadays since most spreadsheets use a format Excel can open. However, if you’re trying to open the document on a pre-2007 Excel program, you can have issues with certain files.

There are two scenarios here:

1. The Excel file is not opening in a legacy version of the program.
2. The file is not opening in Excel because of an unsupported format.

In both instances, the solution is the same. Open any Excel file (or just launch the program and open a blank spreadsheet) and click the File tab. Next, click Open > Browse and locate the file you’re trying to open.

Now, look under the file name field and change the file extension. If you’re trying to open an xlsx document in a legacy Excel version, change the extension to xls. If you’re trying to open a document in an unsupported or less common file format, change the extension to xlsx or xls.

Save the change and then try opening the file again. If everything is done right, the file should open now.

Solution 2. Repair the File

When you get the “Excel cannot open the file because the file format or file extension is not valid” error, it’s likely because the spreadsheet is corrupt. If you manage to open the file anyway, there might be multiple errors and we’re sure you don’t want that. It is better to try repairing the file first and that is exactly what we’re going to do.

1. Open a blank spreadsheet in Excel.
2. Select the File tab and click Open.
3. Hit the Browse button and choose the problematic file.
4. In the file selection window, click the Open drop-down menu and select Open and Repair.

Excel will attempt to repair the file and then open it.

Solution 3. Change Group Permissions

In rare instances, the “Excel cannot open the file because the file format or file extension is not valid” error happened because the file has special permissions. Removing this permission will allow your Excel program to open it without issues.

How do you fix Excel Cannot open the file because the file format or extension is not valid?

How do I verify that an Excel file has not been corrupted?