Something that many programs do is hide information somewhere in the Windows Registry. This is not exactly a file, but you can store some information there.

If this interests you, unfortunately I can't help you with the details; I believe some API functions are involved. I also believe there are some wrapper functions or classes in the download section.

>Hi
>
>I wanted to hide a file. I thought "Windows is the folder. Too many files, not easy to find rare things"
>
>Hide is not an attribute. Hidden among many files. I want to access it if necesary
>
>I wanted to create a folder in Windows... W 7 told me: "KEEP OUT"
>
>Ok. What about "program files" folder?
>
>I tested and I got it. A file was created in "Programs files (x86)" but... I couldn't find it!!! Althought I unchecked "Hide protected files" and checked "show hidden files" Windows 7 search couldn't find it.
>
>However inside VFP it was found? Yes.
>
>Through a third party program I could see my file. It was there. Windows doesn't find it. VFP yes...
>
>Ok. I made the EXE file.
>
>"Access denied"
>
>¿?
>
>The same file is created without problems inside VFP when I execute the final program can't be created.
>
>Can anyone tell me why?
>
>And..
>
>How can I create a file that I want to stay in Windows or another system folder? I don't want to corrupt system. I want to create a file in a common folder.
>
>Obviously I can solve my problem in another way but since this experience I wonder why development yes, executable not.
>
> Héctor