When you encounter a protected Excel table without knowing your password, you can try to solve it by: 1. Use VBA macro to try to unprotect it, which is suitable for weak passwords. The operation is to open the VBA editor and run the specified code; 2. Use file format characteristics to modify the content of the .xlsx file, and achieve it by changing the suffix and deleting the protection tag; 3. Use third-party tools such as Passware to try to crack it; 4. It is safest to contact the file creator to obtain the password. Each method has its own applicable scenarios and limitations.

Sometimes you may need to modify a protected Excel form, but you don't know the password. In this case, there are actually some ways to try to solve it. Although not every situation can be 100% successful, the following methods are feasible in many practical scenarios.

1. Quickly try to unprotect using VBA macros

If the protection settings for tables are relatively simple (for example, using default or weak passwords), you can try using the VBA tool that comes with Excel to unprotect them.

The operation steps are as follows:

• Open the protected Excel file.
• Press Alt F11 to open the VBA Editor.
• Click Insert > Modules in the menu bar.
• Paste the following code:

 Sub UnprotectSheet()
    Dim i As Integer, j As Integer, k As Integer
    Dim l As Integer, m As Integer, n As Integer
    Dim i1 As Integer, i2 As Integer, i3 As Integer
    Dim i4 As Integer, i5 As Integer, i6 As Integer
    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 n = 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
    Ch = Chr(i) & Chr(j) & Chr(k) & Chr(l) & Chr(m) & Chr(n) & _
         Chr(i1) & Chr(i2) & Chr(i3) & Chr(i4) & Chr(i5) & Chr(i6)
    ActiveSheet.Unprotect Password:=Ch
    If Err = 0 Then
        MsgBox "Password cracked successfully: " & Ch
        Exit Sub
    End If
    Next: Next: Next: Next: Next: Next: Next
    Next: Next: Next: Next: Next: Next: Next
End Sub

• Press F5 to run the macro.

This method is effective for weak passwords, but if it is a strong password, the running time will be very long and even not feasible.

2. Use file format features to modify content (applicable to .xlsx files)

If you just want to modify the cell content and don't have to completely unprotect it, you can try to bypass the protection by modifying the Excel file structure.

The operation steps are as follows:

• Change the suffix of the .xlsx file .zip .
• Unzip this zip file.
• Find a .xml file in xl/worksheets/ directory (correspond to the worksheet you want to modify).
• Open the file with a text editor, look for the <sheetprotection></sheetprotection> tag and delete it.
• After saving the file, recompress everything to zip and change back to .xlsx suffix.

This method does not guarantee that all functions can be used, but allows you to modify the content of the table.

3. Use third-party tools to try to crack

There are some tools online that are specifically used to unprotect Excel, such as Passware , Excel Password Recovery , etc. These tools usually support brute force cracking, dictionary cracking and other methods.

Recommended usage:

• Priority is given to software with good evaluation, safe and reliable performance.
• Pay attention to file privacy and avoid uploading sensitive data to online tools.
• For strong passwords, it may take a long time and cannot even be cracked.

4. Contacting a file creator is the safest way

If you do not mean to be malicious, but do need to modify the form shared with you by others, the most direct and effective way is to contact the original author, request them to provide a password or resend the unprotected version.

Basically these are the methods. Each method has applicable scenarios and limitations. If you just want to change a few cells, changing the format may be the most convenient; if you need complete permissions, you may have to try VBA or professional tools.

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