It seems that acs files got corrupt. Make sure you have most recent acs config backup handy.
If you have 3.3 software , you need to go to support folder --->clean----> and run clean.exe.
It will clean all acs components. Now install it back and restore the database and try to upgrade it to 4.1.
Or remove acs setting from registry. Search for acs keyword and delete keys one by one.
Caution : Do it with great care as deleting any other key can cause system to crash. If you have good understanding of registry , then only proceed with it.
Or you can do this exercise on different system and install 4.1 fresh on current system. We need to keep and upgrade existing database that is why we need to follow these steps otherwise it is quite simple
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...