Those lines are all part of a vpn configuration. Are you sure that they are not required by your configuration?
This most likely does not have anything to do with user's ability to use VNC through a VPN connection. Do they have trouble with any other protocols? Can they ping the machines they wish to VNC to through the vpn?
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
[toc:faq]Introduction:This document describes details on how NAT-T
works.Background:ESP encrypts all critical information, encapsulating
the entire inner TCP/UDP datagram within an ESP header. ESP is an IP
protocol in the same sense that TCP and UDP are I...