Repair of Excel file



New Member
Hi - I have a corrupted Excel file which I can't repair. I wonder would any of you be able to repair it? When you open the file writes that "cannot open the file because the file format or the file extension is invalid. Make sure the file is not corrupted and the file name extension matches the format". It's Excel 2010 . Thanks. (Cannot attach the file writes that "The file type you are attempting to upload is not allowed.")


Why am I still doing up?
Have you tried doing CTRL+O in Excel?
Have you tried changing the extension from .xlsx to .xls (or vice versa; sometimes Windows can become stupid in these situations). Don't have Office 2010 anymore (on the latest version) but we get this kind of request a lot @ work which is still 2010.


New Member

When an Excel file is corrupted, then you can try several methods to recover it:

1. First of all, you can try to repair the file manually in Excel, as follows:

(1) On the File menu, click Open.
(2) In the Open dialog box, select the file you want to open, and click the arrow next to the Open button.
(3) Click Open and Repair, and then choose which method you want to use to recover your workbook.

You may find more information about this at: (for Excel 2003) (for Excel 2007) (for Excel 2010) (for Excel 2013)

2. If method 1 fails, there are still several methods to recover your Excel file manually with Excel, including writing a small VBA macro, as below

3. Third, there are also free tools from third-parties that can open and read Microsoft Excel files, for example,

3.1 OpenOffice at This is a very famous open source project that is designed to support Office file formats, including Excel files. The software can run under Windows.

3.2 KingSoft Spreadsheets at This is a free Windows tool that can open Excel files.

Sometimes when Excel fails to open your file, these tools may be able to open it successfully. If that is the case, then after the Excel file is opened, you can just save it as a new file which will be error-free.

4. For xlsx files, they are actually a group of files compressed in Zip file format. Therefore, sometimes, if the corruption is only caused by the Zip file, then you can use Zip repair tools such as WinRAR at to repair the file, as follows:

4.1 Assuming the corrupt Excel file is a.xlsx, then you need to rename it to
4.2 Start WinRAR, go to "Tools > Repair Archive" to repair and generated a fixed file
4.3 Rename back to a_fixed.xlsx
4.4 Using Excel to open a_fixed.xlsx.

There may still be some warnings when opening the fixed file in Excel, just let ignore it and Excel will try to open and repair the fixed file. If the file can be opened successfully, then you can just save the contents into another error-free file.

5. If all above methods do not work, then you may try third-party tools such as DataNumen Excel Repair at

It provides a free demo version so that you can try to see if the data you want can be recovered or not.

Good luck!


New Member
That file is beyond repair. I changed the extension to .XLS and forced it to open up and there is just gibberish inside of it. Do you have a backup or older version you can go back to? Maybe you should try to use the utility Excel Recovery Toolbox?


New Member
Thank you guys for your feedback and help. Sorry, that long time did not respond. This is because the issue was solved and I forgot to tell.) Thank you!


New Member
You can also try Kernel for Excel recovery software to recover your corrupt or inaccessible MS Excel 2010 file. The software is designed with an advanced and secure algorithm to deal with all corruption issues related to MS Excel file. The software is also compatible with both XLS and XLSX file formats of MS Excel. For more information about the software and to download its free demo version, visit:


New Member
There are many manual methods that help you to repair Excel file, so it is worth to try the manual solutions first if it fails than try the automatic repair utility.

Make use of the Open and Repair tool to repair corrupt Excel file.
  • First click on “Open” in the File Menu
  • And from the list, select corrupted excel file
  • Now, from the drop-down list of the “Open” tab, choose “Open and Repair”
  • Lastly, click on the “Repair” button to repair Excel file.
Last edited by a moderator:


New Member
Minor corruption of Excel file is repairable by Open and Repair option. If Excel file is severely corrupted then, here are few solutions:


Open MS Excel in safe mode. If its opening file in safe mode then, delete the COM Add-Ins. To do so,
  • Open MS Excel
  • Go to File->Options->Add-Ins
  • Select COM Add-Ins and remove them.
If it wont help you out then, try Stellar Phoenix Excel Repair software. It repairs all types of corruption from Excel file and comes up with the demo version.
Last edited by a moderator:


New Member
will take note of those suggestions and try to recover my files. I have the same problem too. I have 3 corrupted excel files I need to fix

Katherine Pearson

New Member
For this kind of error, you can try these 2 methods:

#Method 1: Use MS Office Repair Inbuilt Feature

This is an inbuilt feature in the MS office which helps you to repair Excel files easily. But there is another method which helps you to fix “Cannot open the file because the file format or the file extension is invalid” error.

#Method 2: Modification in Excel File Extension

Change the file format of MS Excel file to repair corrupted Excel files. It will definitely help you to repair the workbooks. It's a very easy procedure to change the file extension. Try these steps:

1. Run the MS Excel application in the system.
2. Go to the file tab, select the corrupted Excel file.
3. Click Export option from left-side of the menu bar.
4. Modify the MS Excel file extension into .xlsx.
5. Open the spreadsheet with MS Excel.

Hopefully, above-mentioned methods help you to solve this error and repair corrupted Excel file.

Katherine Pearson


Nice, it might took years for OP to solve his issue with excel, but I guess this will be helpful for others. Lol