How to fix Different format than specified by the file extension in Excel 2010

After upgrading to Excel 2007 or Excel 2010, an error specifying the file you are trying to open .xlsx is in a different format than specified by the file extension when you try to open an excel document:

The file you are trying to open .xlsx is in a different format than specified by the file extension. Verify the file is not corrupted and is from trusted source before opening the file. Do you want to open the file now?

The file you are trying to open .xlsx is in a different format than specified by the file extension

This error occurs when you’re trying to open an XLS file (Excel 2000-2003) with Excel 2007 or Excel 2010.

Quickest way to solve this error (registry)

The quickest way to solve this problem is to insert a registry key. This suppresses the notification.

For Excel 2007, create this key in your registry:

[HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Excel\Security]
“ExtensionHardening”=dword:00000000

For Excel 2010, replace 12.0 for 14.0, as you can see below. Create the following key in your registry:

[HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Excel\Security]
“ExtensionHardening”=dword:00000000

The step-by-step instructions are as follows:

  1. Click Start, click Run, type regedit.exe and press ENTER. This will open your Registry. (Do you have Windows 7 or higher? Then run registry editor as administrator)
  2. Navigate to HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\OFFICE\12.0\EXCEL\SECURITY
    (or 14.0, in case of Excel 2010)
  3. In the right window, Right click and choose New -> DWORD
  4. In the Name field, type “ExtensionHardening”  (without the quotes)
  5. Verify that the data has the value “0”
  6. Click OK. Done!

I advise the steps above to solve the problem. Although it is not the safest option.

Easiest way to solve this error (GUI)

The easiest way to solve the error The file you are trying to open .xlsx is in a different format than specified by the file extension is to use the Options screen in Excel 2010. Follow these steps to disable the warning message:

  1. Open Excel 2010. Click on File, and go to Options.
  2. Click on Trust Center at the left. Then click on Trust Center Settings in the right window.
  3. In the new window Trust Center, click on Protected View on the left side panel
  4. Uncheck all options:
    1. Enable Protected View for files originating from the Internet
    2. Enable Protected View for files located in potentially unsafe locations
    3. Enable Protected View for Outlook attachments
  5. Click OK (2x). Done!

Back in 2008 I advised people to properly configure MIME Types to resolve this issue. However the issue does not occur in later versions of Office (2013, 2016 and so on). Therefor it doesn’t feel necessary anymore. This is what I stated 10 years ago: If you want a more constructive way, you should define MIME types and associate them with extensions.
Do you use a Document Management System like Sharepoint or Livelink? Try adding these:
.xls = application/msexcel
.xlsx = application/vnd.openxmlformats-officedocument.spreadsheetml.sheet

Fix The file you are trying to open .xlsx is in a different format than specified by the file extension with Group Policy

As an administrator you may want to consider the option to deploy the registry settings with a Group Policy Preference. I have not written a step-by-step guide to do this yet, but you may find this blog post about deploying WIFI-profiles with GPO Preference interesting and helpful.

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Amber Bhatnagar

Hi,

Your solution really worked.Its excellent.

Thanks,

Amber Bhatnagar.

Vasanth

Hi ,

I have already tried the above solution , it’s working. But i want the solution in the way that from the jsp code. If you find any solution
i will be very happy.

Thanks,
vasanth.

Ted

Thanks a lot.

Samita

Its working!!!!! wonderful….

Rebecca

Thank you! As a non techie…your instructions were great! It took care of the problem.

Saravanan

Thanks for solution

Far

hi
ive tries your trick , now i m not getting the error msg , but file is still corrupt all i c is special character but no data.
can u help me with that
thank u

zlatan24

I heard about not bad application-xlsx repair Microsoft, know how will display a dialog box with the question whether this worksheet should actually be scanned, also with help it you may try to open the necessary *.xls, *,xlt, *.xlsx, xlsm, *.xltm, *.xltx, *.xlam file and see an error message on the screen instead of it: Microsoft Excel unable to read file, This file is not in a recognizable format, etc.

Anonymous

THANKS!!, IT REALLY WORKS.BEST REGARDS.

Thanks for solution

thanks for you friend but I use and try it

Thanks a lot.

Hey Thanks For it Awesome its working

Hi ,I have already tried the above solution , it’s working. But i want the solution in the way that from the jsp code. If you find any solutioni will be very happy.Thanks,vasanth.

Hi,Its working.Thanks,Devendra Patil,Jalgaon

Hi,Your solution really worked.Its excellent.Thanks,Amber Bhatnagar.

anon

Thank you so very much. I’ve been pestered by that annoying pop-up for months; I deal with a very large number of Excel files that don’t have an extension and constantly throw this error. This has seriously given me 5 minutes of my day back.

Ranjan ROy

Thank pal..It really hepled me

Trevor

Hi I tried adding HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\OFFICE\12.0\EXCEL\SECURITY
but my excel documents are still corupt. any help please

Ahmad

I don’t have security folder. I added the same under ..\EXCEL\ folder and it didn’t work

Sreekanth

Inspite of setting the ContentType for XLS as well as XLSX…I am getting the same problem with the weird mesg “Different format than specified by the file extension”

Any help is highly appreciated

-Sreek

Sashikant

Thanks God….Its working..Thanks to UUUUUUUU too

Umesh

I tried above solution and it works fine for me. But i don’t want to do any changes in registry .Is there any other solution ?
I am using c# and asp.net 2.0 . Here i am export grid view in excel file and when i opened excel file that time above warning message i am facing .

Regard,
Umesh.

Jayesh

No complicated reg settings or modifications, just rename the .xls extension to .xlsx, you are done.

Ankit

nothing worked.. all tried .. changed .xls to .xlsx and changed in registry as well.
Any other solution..

Jon

This error is commonly caused when .SaveAs VBA code (or export from an application) specifies the file should be created as filename.xls whilst saving in 2007 (i.e. xml) format. When this file is then opened: – In Office 2007 you get the format file extension error but it will open and work fine – In Office 97-2003 the file will open but will appear corrupted as 97-2003 cannot interpret xml files The solution from a macro perspective is to modify the code to specify the file format by adding the following code if you need to share with people on… Read more »

venkat

Even changed the setting the ContentType for XLS as well as XLSX
I am getting the same problem with the error mesg “Different format than specified by the file extension”

Jon Where I have to add code “FilFormatNum” , cna you please give examples

Surender

I had changed the registry values as suggested. I could able to open the files
without any error this is great and I am getting a blank worksheet and I am worried about my data. Any work around this to retreive my data back.
Thanks,
Surender.

acrwebline

Do you have a solution for Vista? The registry values as explained must be in XP only, because the information is not found in the visa registry. Can you confirm. Thank you.

Kesavan

We tried by setting in registry. Its working fine.
Eventhough is there any other way?.
Pls advice.

Yawar Abbas

hi
ive tries your trick , now i m not getting the error msg , but file is still corrupt all i c is special character but no data.
can u help me with that
thank u

Kesavan

I will try in all the possible cases and let you know.

zafar

sir
i have tried your trick, file become open with out any error but the content of file become changed in 0 1 and others alphabatic, please hel me out

rigo

THANKS!!, IT REALLY WORKS.
BEST REGARDS.

Sridhar Gumpula

Hi,
wow great solution its working fine
thank you for your solution

Sridhar Gumpula

Ghazanfar Ali Bhatti

thanks for you friend but I use and try it

Jitendra Kumar

it really worked for me.Thanks for the solution

Ananth

This really works !

Thank you,

Ananth

Abdul

Thanks a lot… this save my day 🙂

Devendra Patil

Hi,

Its working.

Thanks,
Devendra Patil,Jalgaon

Jay

Excellent! Thank you so much for this solution.

yogeesh

Hi,

the solution really worked.

Thanks,
yogeesh.

Maher

hello..my excel worksheet writes the following:c+-B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B€‘©{‘øÑ‘û1‘

so how can i repair the data that has been lost,,
and there is any way to translate this symbols to the original data that Ive inputted it????

please help.

Anonymous

hello..my excel worksheet writes the following:c+-B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B€‘©{‘øÑ‘û1‘

so how can i repair the data that has been lost,,
and there is any way to translate this symbols to the original data that Ive inputted it????

please help.

phoeneous

This works great, thank you!

Ahmed

Hello i cannot open my excel file it was working fine suddenly it shows this error. I tried the way which you had mentioned above but doesn’t work out.
:c+B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B€‘©{‘øÑ‘û1‘

Please advise how can i fix this file.
Any software or translator or any other way to change the extention to open and recover my data.

Please reply.

Thank.

vanitha

Thank you so much. I have inserted ExtensionHardening key in my registry. It is working fine with out any issue.

Viji

It worked fine ,Thanks

p

It worked! thx in Win7 too.

Atiq Juma

FILE OPEN IN THIS FORMAT ( I HAVE SAME PROBLEM IN EXCEL AND WORD)

c+B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B!„B

Please advise how can i Open my file.

Any software or translator or any other way to change the extention to open and recover my data.

Please reply.
Thank.

srinivas

Dear sir, The file you are trying to open .xlsx is in a different format than specified by the file extension. verify the file is not corrupted and is from trusted source before opening the file. This problem that i am facing. So please give me suggest . this is very important to us. So please help me sir. this is my Humble request for u. please reply me. i want suggestion from u. help me plz. even i tried the procedure. which u gave in the website but its not working. plz help me sir. i wish u will… Read more »

NOBLE

Sir,While opening the file we receives the content which was low level format example ” ªdÕ /1éƒO@üôâVR-D«›°‰)¿:5Ë«±Ï!œn¶h%P¹Þ.Þy¼äÞXÎàš43€x©õJÉ<ÁHl-&ð´æ)Tm á ‘Gí€=mm`„µ„ þ “….please suggest in this regard.Thanks, Ali. Dear sir,The file you are trying to open .xlsx is in a different format than specified by the file extension. verify the file is not corrupted and is from trusted source before opening the file. This problem that i am facing. So please give me suggest . this is very important to us. So please help me sir. this is my Humble request for u. please reply me. i want suggestion from u. help… Read more »

Arturo Gutierrez Cruz

It work excellent, thanks for the help

Brian

I was getting the error like file format is not specified after opening the 2003 macro excel file in 2007 excel. After doing the steps given above , error message is not coming but excel sheet gets disappeared after complete processing. Please advice.

shrishail

Hi
your solution woked.It is very nice

Janet Huang 1965

Thank you so much for the fix. Worked great!

Janet

Anonymous

Not at all working>Janet

HiPlease give the proper solution

Thanks

Thank you so much for the fix. Worked great!Janet

Sherri

I’m having this issue with a file when I open it. Your solution looks good, but won’t it only work on my laptop? What can I do if my file is going to be opened by others on different computers?

younes

I’m having this issue with a file when I open it. Your solution looks good, but won’t it only work on my laptop? What can I do if my file is going to be opened by others on different computers?

that would be their problem and not yours.

Mike

I love you.

Gamecock

Great fix! Thank you so much!

Nikita

I was gettibg the same error, the regedit jhelps to erase the error but still the data is incorrect. It gives some corrupt junk data.
Can u help please?

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