Hi Vaibhav, I was shocked to hear that u're just 14! You invented the code yourself? If that's true, then u're a genius! Way to go! Anyway, i discovered some 'Problems' in your code(not bugs). First, if a person has access to your code, then its as simple as a pie for him to discover the password and moreover if he is a bit too geeky then he can altogether do away with the password prompt too. Second, if a person boots the computer with a Linux Boot CD or with any other OS except any Windows OS then he/she can easily access the files in the folder. Another 'Problem' I found was that if you loacked a folder on your USB and connected it to another computer, then the folder is visible. Also, you cant lock a folder with a Limited Account.
I hope you may be able to rectify them if you are revising ur code for another program in the future.
PS: I'm 17 yrs old (Turned 17 this August)