The error message is indicating that XAUTH is configured on your side and not configured on the other side. It can work if both sides are configured for XAUTH or if both sides are not configured for XAUTH. The suggestion from Theo to check and make sure that the key configured on both sides is the same is a good suggestion. But I do not believe that you have gotten to that stage yet.
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...
Table of Contents 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 an...