There is many good calls you can use in the windows system dll files

But beware.. the program/game you making is much more easy to crack then

But what tha f*ck, just encrypt/pack the program with another packer/encrypter than DBPros. And when you already up to it.. make some anyoing check code to in your program just to f*ck with crackers who want to sc*ew your program/game.
And by the way

cracking a home made/commercial game/app is much more simple than anyone thinks it is.. how I know this?! Dont ask
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