security - Is there some sort of secure local storage on Windows?

Question

I was thinking of making a small tool. It is not important what the tool will do. The important thing, is that the tool will need to store some sensitive information on the user's HDD. EDIT: The information that will be stored is USER'S information - I'm not trying to protect my own content, that I distribute with the app.

I understand that I need to encrypt this information. But then, where do I safely store the encryption password? It's some sort of an infinite recursion...

So, is there a way, to encrypt information on windows, and have windows securely manage the passwords? When I say windows I mean Windows XP SP2 or later.

I should also note, that users on the same system must not have access to other users information (even when they are both running my application).

I'm looking for both - .NET 2.0 (C#) and native (C/C++) solutions to this problem.

Answer 1

is there a way, to encrypt information on windows, and have windows securely manage the passwords?

CryptProtectData: http://msdn.microsoft.com/en-us/library/windows/desktop/aa380261(v=vs.85).aspx

Using from .NET: http://msdn.microsoft.com/en-us/library/aa302402.aspx

Historically, Protected Storage (available in XP, read-only in vista+): http://msdn.microsoft.com/en-us/library/bb432403%28VS.85%29.aspx