Lock any folder without using any software in Windows

1. Suppose you have a folder named test in D:\test.

2. In the same folder-level, create a new notepad file with the exact statement
ren test test.{21EC2020-3AEA-1069-A2DD-08002B30309D}

3. Now save this text file as lock.bat

4. Create another notepad file and type
ren test.{21EC2020-3AEA-1069-A2DD-08002B30309D} test

5. Save this as key.bat

6. Now there are two batch files. Double click lock.bat and your folder icon will be changed to Control Panel and its contents cannot be viewed .

7. To open the folder double click key.bat and you get back your original folder.

8. For more safety keep the key.bat in another location .For unlocking copy paste to the original location and double click.