The technical reason every Windows lock app fails — and how I fixed it at 13.

Every. Single. One. Same result.

Why does this happen?

Because every lock app protects at the
application layer.

The OS still runs underneath.
Task Manager still works.
Process killing still works.

To actually prevent bypass — you need to go deeper.

How ATLOCK goes deeper

1. WH_KEYBOARD_LL Hook

Windows provides a low-level keyboard hook that
intercepts keystrokes before any app processes them.

keyboard_hook = ctypes.windll.user32.SetWindowsHookExW(
    WH_KEYBOARD_LL, 
    keyboard_proc, 
    None, 0
)

This blocks:

  • Alt+Tab (switch apps)
  • Win key (open start menu)
  • Alt+F4 (close window)
  • Escape

Not at app level. At OS level.

2. Task Manager Watchdog

A background thread runs every 500ms:

def watchdog():
    targets = ['taskmgr.exe', 'procexp.exe', 
               'procexp64.exe', 'processhacker.exe']
    while lock_active:
        for proc in psutil.process_iter(['name']):
            if proc.info['name'].lower() in targets:
                proc.kill()
        time.sleep(0.5)

Task Manager opens? Dead in half a second.

3. Focus Enforcement

Continuous loop prevents lock screen from being
pushed to background:

while lock_active:
    window.focus_force()
    window.grab_set()
    time.sleep(0.1)

4. NTFS ACL File Guard

Files locked at filesystem level using Windows
Access Control Lists:

subprocess.run([
    'icacls', file_path, 
    '/deny', 'Everyone:(F)'
], capture_output=True)

Not even administrators can touch protected files.

The result

Two exits only:

  1. Correct password
  2. Timer expires

Nothing else works. Not Task Manager.
Not Process Hacker. Not restarting Explorer.

Who built this

13 years old. India. Solo.
Under Akhouri Systems.

123+ real downloads. No marketing budget.

Free. Single .exe. No Python needed.

https://github.com/Akhouri-Anmol-Kumar/ATLOCK

We build what others forgot to fix.

Leave a Reply