adobe flex copies over user files after terminate debugger

Question

I am uing Flash Builder 4.0.1 under Windows 7.

My application write to files in documentsDirectory (the program reads and writes to files in a subdirectory of "My Documents"...):

        var trFile:File = File.documentsDirectory.resolvePath(name);
        var fs:FileStream = new FileStream();
        fs.open(trFile, FileMode.WRITE);
         _buff = what ever ...
        fs.writeUTFBytes(_buff);

Before I close the debugger, I see that the program wrote correctly to the files. However, when I stop the debugger Terminate command (Run/Terminate), the flex/flash debugger copies over my files in this (user directory). Why is this happening? How can I stop it from doing so?

Thanks