Can't get User Impersonation to work with network drive

Ok I'm trying to get the following to work with VS 2010 & Win 2K8 Server:

[Security] - User Impersonation[^]

If I use a local folder it works fine, but when I choose a network mapped drive I get the following:

Result:
        Failed to open the file, error: 3
        The system cannot find the path specified.

I have coded in the user name, password, domain and file and made the following change in main:

// We support a user name, password, domain (optional) and filename (optional)
if((argc < 3) || (argc > 7))
{
    Usage();
    //return 0;
}

The reason I'm trying to get this to work is we are working on implementing security for our network (There's an idea huh), and our senior programmer likes to have everything is one big giant directory so we are trying to restrict user access to certain folders, but by doing so our applications won't work. So we would like to give the application the "rights to do so" and this seems like the best way, but I can't get it to work on mapped drives.

Not sure if it matters but this is in a terminal services enviroment.
Thanks in advance!!

Tags: C++