a question about the impersonate an user

hi my problem is, I have a window server 2000 with IIS 5.0, I am now using .net 2k3 as my development tools. I am now try to copy some xml files from Server 2000 to another client machine in XP os. We are in different domain. So I wonder can someone guide me how to do that. What kind of user account do I need to create in Client machine. Let say in client machine there is a shared folder called "Shared".Also How to do it in behind code. Thanks

 
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