So those should take care of the "Configuration" questions.
As for Authentication: Out of the box, QlikView uses standard Windows Authentication. Should you be moving domains, then what you need to look out for is the service account requirements (local administrator, access to all QlikView files, member of QlikView Administrator group), as well as watch out how users have been given access. For moving over bookmarks, etc, see How to: Transfer server bookmarks between servers, domains, or users (though I am not sure if this is relevant in your situation).
If, on the other hand, you have integrated QlikView with a different identity provider, then you'd need to look into the configuration of that and redo it where necessary. This is not something I can give you any advice on, it'd be best to speak to whoever is in charge of the implementation on your end.
As for Access from Outside Network: That'd have to be looked at by your network administrators. So, do they need to adjust firewall rules, NAT rules, DNS records, etc.. to point at the new machine. QlikView will just sit there on its new machine and listen on its ports, it's up to the rest of the network to tell the users how to get there.
If you need assistance with any of the above, we have very knowledgeable consultants and expert services available to help you plan and execute on this.
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