Monday, 13 August 2007

Microsoft Excel File Password Recovery

Ever had a file that has a password and unable to open it. I recently faced the similar situation. I was forwarded a mail with a puzzle and the answer of the puzzle itself is the password of the Excel file. I tried to solve the puzzle but couldn't do it. So, I thought of finding password recovery software. I would like to share you about my findings.

Actually Microsft Excel docements utilizes three passwords.

  • Password to open
  • Password to modify
  • Protect workbook or sheet

The first one needs to enter the password to view the document. Once the password is set, Excel encrypts the whole document with RC4 stream cipher. The second one needs to enter the password when we need to modify the file. The Protect sheet or Protect workbook password requires the user to enter a password to unprotect the either the worksheet or the workbook. You can find information on setting the password and other information here.

Recover Microsoft Word / Excel file Passwords

There will be two situations dealing with password encrypted files. The file is

  • Opened currently and want to know the password
  • Closed and want to know the password

Situation 1: File Currently opened :

In this situation, you have the file currently opened and want to know the password for accessing the file in future. You can change the password but instead want to know the password that was set already, then you need "Excel Password Remover 2007". This is a Excel add-in that works fine in Excel 5.0 or above (including Excel 2000, XP and 2003). Just open this add-in and enable Macros before opening this. This add-in adds two entries in Tools Menu.

  • UnProtect Workbook
  • UnProtect Sheet

These two entries help you in removing the password. You can download this add-in Excel Password Remover 2007. Read this link for more instructions on its usage.

Situation 2: File Currently Closed :

The file is unable to open and is asking for the password. You need to try this Microsoft Word / Excel password recovery software wizard. It's a 300kb zipped file which has the wizard and other readme files. After installing .msi file, you have the wizard and can easily retrieve the password. It has two options. Either  you can give the password dictionary or else it has the bruteforce method of finding the password. It is very convenient and simple to use. You can find the software at You can download at this site.

I used the bruteforce option for my  password retrieval and finally got succeeded.

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