Protect a Folder in Windows Xp:

1. First select the folder which you want to protect: (For example D:\movies\)

2. In the same drive create a batch file and type the following
ren movies movies.{21EC2020-3AEA-1069-A2DD-08002B30309D}

3. Save it as lock.bat

4. To unlock the folder create a another batch file in the same directory as following
ren movies.{21EC2020-3AEA-1069-A2DD-08002B30309D} movies

5. Save it as unlock.bat

6. Now in D drive u can see two batch files Lock and Unlock. When u double click Lock the movie folder will change to control panel and whn u double click Unlock the control panel will change to normal folder..