Sometimes the "excel file cannot open because file format or extension is not valid" can irritate you as you did nothing wrong. Luckily, if you are facing this issue only with one Excel file, you will not have to do a lot. The solution for you will be simple, and here are our top 5 ways you can solve this issue.

excel file or extension not valid

Part 1: Causes of Excel Cannot Open with Invalid Format/Extension

Microsoft Excel is an important tool for businesses and individuals because it efficiently manages data in the form of sheets. However, sometimes you get a "excel file cannot open because file format or extension is not valid" error. It can be because of so many reasons and issues at your end and where you are getting the file from. Some of the causes for this error are:

  • A corrupted file.
  • Having the wrong extension.
  • The difference in excel versions.
  • Unsuccessful downloads.
  • Damaged file.

Part 2: Solutions to Fix Excel Cannot Open the File

We know how important that excel file might be for you. Most of the time, people looking to solve the "Excel file format/extension is not valid" error want to ensure that they will not lose the important data they have in the file. If you also want the same, you can rely on the following solutions.

These solutions will help you eliminate the "Excel file cannot open because the file format or extension is not valid" error and all such errors.

Solution 1. Changing to Another File Extension

The first solution to the "Excel file format/extension is not valid" error is simple. There is not much you will need to do for this method, and below are all the steps you need to follow.

Step 1.Open Microsoft Excel: So, you will start by opening Microsoft Excel on your computer and going to the files section.

Step 2.Change File Settings: Click on Export from the list, and you will see another list. You need to click on Change File Type and then select the file with an error.

change excel file type

Step 3.Save File: The last thing you need to do is Save the file, and the issue will be gone.

Solution 2. Recover Unsaved Workbooks

If you get the "Excel file cannot open because the file format or extension is not valid" error, then recovering may help you get rid of it. This solution is a little bit longer than the previous one. So, be careful when following these steps.

Step 1.Go to files: First, you will need to open Microsoft Excel and go to files, and then to Info.

Step 2.Manage the workbook: Next, open the Manage Versions and go for the Recover Unsaved Workbooks option.

recover unsaved workbooks

Step 3.Recover and save: Now Microsoft Excel will automatically look for the files and recover them. All you got to do is to save your target file, and you will be good to go.

Solution 3. Restoring Previous Version of Excel File

Did you know that restoring files to previous versions can sometimes solve the errors like "Excel file cannot open because file format or extension is not valid"? Here we will be telling you how to do this to make your Excel file work again.

Step 1.Search for the file in file explorer: Open the file explorer and look for the file that you are unable to open.

Step 2.Open properties: Once you locate the file, open its properties by right-clicking and then go to the previous version tab.

go to properties of invalid excel file

Step 3.Select the version that you want: There will be a list of previous versions. Go for the one that you want and click on OK.

restore previous version

These simple steps must resolve the issue at your end.

Solution 4. Using Open and Repair Feature

Yet another simple but ingenious solution to get rid of the issues you are facing with excel files. Here are the steps that you may need to follow.

Step 1.Open Microsoft Excel: Open MS Excel and go to the files section, then go to Open.

Step 2.Locate the file in the browse option: Go to the Browse option and look for the file.

Step 3.Go for the Open and Repair option: Find the file, select it and on the open button, click on the dropdown, then select Open and Repair.

open and repair excel file

Solution 5. Repair Corrupted Excel File

The ultimate solution to the "Excel file format/extension is not valid" error and all such errors are using the iMyFone UltraRepair tool. It is a tool that comes with a long list of features to meet all your file repairing needs. The best part about using it is the premium experience that you can have here. Below are some of the best features of the iMyFone UltraRepair tool.

  • Fix any file within seconds: When you get errors from your Excel file, the iMyFone UltraRepair tool will not take more than a few seconds to repair the issue.
  • No more than 3 steps are needed: With the iMyFone UltraRepair tool, you will only need to focus on 3 simple steps. Uploading, repairing, and saving your files. In this way, the process will be extremely simple and convenient.
  • Do much more than repairing Excel files only: iMyFone UltraRepair tool is made to deal with all your file repairing issues. Here you can repair excel files, other documents, pictures, and videos.
ultraRepair_icon iMyFone UltraRepair - Repair File

UltraRepair gives you the best solution to repair your broken files including Word, Excel, PDF, and all the other formats.

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Step 1. Download and open iMyFone UltraRepair on your PC. Then navigate to the "File Repair" area on the left side of the software and click the "Add Files" option. It will launch a browser window and show where the corrupted file was stored.

use ultrarepair

Step 2. The software will import Word files from your PC and show the process on the screen. If you accidentally uploaded the incorrect file, you may remove it by hitting the trash can symbol next to its data.

save repaird files

Step 3. The software will scan the loaded document and correct any large or small errors. You can also stop the repair at any moment. When the file repair operation is finished, a pop-up notification will display that will alert you of the repair results. A file that has been successfully fixed will have a "Success" indicator beneath it.

save repaird files to your pc

And it’s done.

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FAQs: More About Excel File Cannot Open

1. What happens if excel file format does not match file extension?

When the excel file format does not match the file extension, it means that the file that you are trying to open has a different file extension. This file extension is currently hardwired, and this is the reason why you are facing this error and are unable to open the file.

2. What can I do when excel running slow?

There could be many reasons for Excel running slow. So, the best method is to find the cause and then solve it. In most cases, updating solves the issue, but sometimes you need to try other solutions.


When you fix the Excel file format/extension is not valid error, you will be able to use that Excel file without losing any of the data or information it holds. Make sure to try these solutions as any one of them may work out for you. If you want the most convenient experience, then going for iMyFone UltraRepair is your best choice.

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