This is odd one, I'm running Windows Vista on a test laptop for work. The Cisco Client seems happy to connect from our test DSL connection in the office and from my EVDO card. But at home I get the 412 remote peer no longer responds crap. I tried wired and wireless, changed my MTU to 1500 and 1300 on both my router at home and by client. Tried using TCP port 10000 (which is setup on the ASA) and UDP, the logs dont show anything blocked.
I'm using a D-Link DGL-4300, I have gotten my WinXP box to connect from home. Work we are using an ASA 5520.