How to lock folders without using any software

Here are the steps to lock (not actually lock but to change the pointer address) a folder in windows xp:

1. Assume I want to lock a folder named 'new' which I have created in c drive.
2. Go to the path (in this case its c:\) create a new notepad entry.
3. Then edit that entry by typing in it the following:
ren new new.{20D04FE0-3AEA-1069-A2D8-08002B30309D}
4. Save it as lock.bat
5. Now if you run the .bat file your icon 'new' should have changed. Try clicking it now.
6. For creating a key, open an other notepad entry and write:
ren new.{20D04FE0-3AEA-1069-A2D8-08002B30309D} new
7. Save it as key.bat and run it.

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