Hey there, let's work through this Excel password headache together. I’ve helped folks with similar issues before, so here’s what you can try:

Your idea of using a new workbook to run code against m.xlsx is totally doable—you don’t need to "replace" THISWORKBOOK; instead, you’ll directly target the locked file via its path. Here’s a script that tries two approaches:

Sub UnlockWorkbookStructure()
    Dim targetPath As String
    Dim wb As Workbook
    
    ' Replace this with your full file path to m.xlsx
    targetPath = "C:\Your\Folder\Path\m.xlsx"
    
    ' First try: Directly open and unprotect (works for weaker protections)
    On Error Resume Next
    Set wb = Workbooks.Open(targetPath, Password:="")
    On Error GoTo 0
    
    If Not wb Is Nothing Then
        wb.Unprotect Password:=""
        wb.Save
        wb.Close
        MsgBox "Success! Workbook unlocked."
    Else
        ' Fallback: Copy all sheets to a new workbook (bypasses structure protection)
        MsgBox "Direct unlock failed—creating an unlocked copy instead."
        Dim newWb As Workbook
        Set newWb = Workbooks.Add
        
        ' Copy every sheet from the locked workbook to the new one
        Dim ws As Worksheet
        For Each ws In GetObject(targetPath).Worksheets
            ws.Copy After:=newWb.Sheets(newWb.Sheets.Count)
        Next ws
        
        ' Delete the default blank sheet in the new workbook
        Application.DisplayAlerts = False
        newWb.Sheets(1).Delete
        Application.DisplayAlerts = True
        
        newWb.SaveAs "C:\Your\Folder\Path\Unlocked_m.xlsx"
        newWb.Close
        MsgBox "Unlocked copy saved successfully!"
    End If
End Sub

• How to use: Open a blank Excel workbook, press Alt + F11 to open the VBA editor, insert a new module, paste this code, update the file paths, and run it.
• Note: This works for workbook structure protection (e.g., can’t add/delete sheets). If your file requires a password just to open it (full encryption), this won’t work.

Excel files are just zipped folders with XML files inside. For structure-protected workbooks, we can remove the protection tag directly from the XML without opening the file in Excel. Here’s a Python script to do that:

import zipfile
import os
import shutil
import re

def unlock_excel_workbook(file_path):
    # Create a temporary folder to extract the Excel contents
    temp_dir = "temp_excel_unlock"
    os.makedirs(temp_dir, exist_ok=True)
    
    # Unzip the Excel file into the temp folder
    with zipfile.ZipFile(file_path, 'r') as zip_ref:
        zip_ref.extractall(temp_dir)
    
    # Locate and modify the workbook.xml file
    workbook_xml = os.path.join(temp_dir, "xl", "workbook.xml")
    with open(workbook_xml, 'r') as f:
        content = f.read()
    
    # Remove the workbookProtection tag that enforces structure locks
    content = re.sub(r'<workbookProtection[^>]+>', '', content)
    
    with open(workbook_xml, 'w') as f:
        f.write(content)
    
    # Repackage the contents into a new unlocked Excel file
    unlocked_filename = f"unlocked_{os.path.basename(file_path)}"
    with zipfile.ZipFile(unlocked_filename, 'w', zipfile.ZIP_DEFLATED) as zip_ref:
        for root, _, files in os.walk(temp_dir):
            for file in files:
                file_path_in_temp = os.path.join(root, file)
                relative_path = os.path.relpath(file_path_in_temp, temp_dir)
                zip_ref.write(file_path_in_temp, relative_path)
    
    # Clean up the temporary folder
    shutil.rmtree(temp_dir)
    print(f"Unlocked file saved as: {unlocked_filename}")

# Replace this with your actual file path
unlock_excel_workbook("C:\\Your\\Folder\\Path\\m.xlsx")

• Key notes: This only bypasses structure protection. If your file is fully encrypted (requires a password to open), this method won’t work—full encryption locks the entire zip package, not just individual XML files.
• Always back up your original m.xlsx before running this!

• If you’re dealing with a password required to open the file (full encryption), these methods won’t help. Brute-forcing such passwords is slow, unreliable, and may violate terms of service or laws—your best bet is to try to recall the password or use a dedicated (legal) password recovery tool if you have proper ownership.
• Always test these methods on a copy of your file first to avoid data loss.

内容的提问来源于stack exchange，提问作者Ray