I'm going to leave this rather broad, let me know if I need to be more specific...
What I'm building is an application, which allows users to copy files to an NT machine on the network. This program will have many users, some may have access permissions to the target machine, but most will not. Is there a way through code, to impersonate a user with adequate permissions to make the copy? I'm not sure if network protocol is significant but our LAN is TCP/IP. Client machines may be Win95, Win98 or WinNT, while the target machine is always going to be WinNT.
Any documentation, mention of APIs would be great. Code snippets would be cool, but not neccessary.