Breaking Excel password protection

If you came across an excel sheet asking for password for allowing to make any changes into it, you may want to unprotect it.
All we need to do is to edit the xml file which comes intrinsically packaged with Excel 2007 or 2010. But what about Excel 2003? For that, open the Excel 2003 file within Excel 2007, save it as xlsx file. So, keep in mind all the Excel files below 2007 version, you need to convert them as Excel 2007 with extension .xlsx.
Now here are the steps for doing that:
1. Open the Excel 2003 file (e.g. Secret.xlsx) and save it as .xlsx (Excel 2007) format. If you already have Excel 2007 file, then no need for any conversion.

2. Now change the extension of the above file to .zip and extract the zipped file. Browse through the file in the extracted folder and go to:
<LocalPath>\Secret\xl\worksheets.
 
3. Now open the sheet/ sheets you want to remove protection in any xml editor. Look for keywords such as 'sheetProtection' or 'workbookProtection' in the xml file.
Remove such lines entirely from the xml files above. Do this for all the sheets you want to remove the protection.

4. Now, copy all these edited and saved xml files to the original zip file under the same path. Now change the extension back to .xlsx from .zip. You are done!

Comments

Anonymous said…
I tried your suggestion. But it did not work. After saving it as an xlsx file, I rename the file to a zip extenstion.

That is where I start having a problem. The file fails to extract stating its an invalid file.
Nilesh Kumar said…
@ Anonymous,
Seems you file is an Excel 2003 file.
As I have mentioned in the blog, this only works for Excel 2007 or 2010 with .xlsx extension. If the file is Excel 2003, you need to open it with Excel 2007 and save it with .xlsx extension.So, keep in mind all the Excel files below 2007 version, you need to convert them as Excel 2007 with extension .xlsx.
Let me know if that helps.
Thanks,
Nilesh
Anonymous said…
How can you open a password protected Excel 2003 file with Excel 2007 and save it with .xlsx???? If a file has a password, you can't open it!!!!!!!!
shekhar said…
i have a file in excel 2007 password protected i cant open beacuse forget password i am very thankful if u help me in open i send u a file on your email id

regards
shekhar
Anonymous said…
Dear I have an excel 2003 sheet which is password protected and I can not open it. I have tried the brute forcing software but it takes hell lot of time. is there some simple way to remove the password
Anonymous said…
That worked very well. Hard to believe that the "protection" was that easy to crack. Why in the heck would anyone use a code cracker to try and guess the password when this method took me all of 10 minutes from start to finish, and that includes the time it took to download a zip file program? Thanks for the tip.
FGSouza said…
The method works to unprotect a spreadsheet. However how can I, (after have unprotected the sheet and made my modifications), return the protection with the same password that was before? Any ideas?
Abhishek said…
Thanks a lot Nilesh. I tried and it worked.
Anonymous said…
didn't work for me. Is there a 2006 version of Excel? I think that's what mine is
RenĂ© Jensen said…
Works fine
Can you get the password to?

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