Unprotect locked Excel spreadsheets using macro

Today in my service, I had to unlock an excel spreadsheet to edit some fields that those who protected, did not develop correctly, and were displaying incorrect values, so I ran across the web to look for something, and found a method by creating a macro.

The spreadsheet was in Office 2007 format, but it is possible to save for Office 2003 in compatibility mode. The computer I used to try to do the trick was Windows XP with Office 2003.

Due to a very simple security flaw, it is possible to add any macro to any type of spreadsheet in Office 2003, including protected ones. With a macro, from which you can insert it into several protected worksheets, you can quickly unlock it. For this, you must keep on the protected sheet, go to the Tools> Macro> Macros ... menu or simply press ALT + F8.

The macro creates a loop using all possible passwords, as excel has no limit on attempts, and attempts on a local computer are extremely fast than on internet services, all possible passwords are tested and the spreadsheet is unlocked, removing the password.

For those who do not know, the feature of protecting spreadsheet, serves to keep the data as "read only", fields, functions, among others, preventing modification without the correct password.

Being protected, the person who wants to change any protected field, an alert message will appear as below:

Step by step:

Create a new macro with the name: UnprotectPlanilhaAtiva.

Soon after, an editable window will appear with two lines filled in as follows:

Between the two lines, insert the code:

Dim i,i1,i2,i3,i4,i5,i6,j,k,l,m,n:On Error Resume Next:For i = 65 To 66: For j = 65 To 66: For k = 65 To 66: For l = 65 To 66: For m = 65 To 66: For i1 = 65 To 66: For i2 = 65 To 66: For i3 = 65 To 66: For i4 = 65 To 66: For i5 = 65 To 66: For i6 = 65 To 66: For n = 32 To 126: ActiveSheet.Unprotect Chr(i) & Chr(j) & Chr(k) & Chr(l) & Chr(m) & Chr(i1) & Chr(i2) & Chr(i3) & Chr(i4) & Chr(i5) & Chr(i6) & Chr(n)

If ActiveSheet.ProtectContents = False Then   MsgBox "Planilha desprotegida com sucesso!!!": Exit Sub
End If: Next: Next: Next: Next: Next: Next: Next: Next: Next: Next: Next: Next

Close the Macro editing screen and return to your excel spreadsheet. Press ALT + F8, select the "UnprotectPlanilhaAtiva" macro and click "Run".

The macro remains inside the protected worksheet, click on the desired worksheet, and using the ALT + F8 command, execute the macro. Wait until the confirmation window from which you were unprotected appears.

The bigger the password that was created, the longer it takes for the code to be executed, that is, do not worry if it happens "Not responding", because in reality, the code that is being executed, usually consumes processor resources , and Windows identifies that this generated an infinite loop, but it is not infinite, and does not last more than 30 seconds with a 17-digit password (tested).

Source: http://www.guiadohardware.net/comunidade/desproteger-planilha/299297/