I have the same problem. Cisco SA520, I switched my infrastructure last week from ADSL to cable and my ISP requires that I use L2TP dialer to connect, which does not work on the Cisco.
In my case I do have a fixed IP address (I still get it automatically from the ISP, I just get the same address every time), so I even tried to put this fixed IP in the "My IP address" field of the IPv4 configuration, but it still doesn't work. Maybe the ISP waits for the router to make a dhcp request before enabling the connection, not sure.
For now I brought a cheap router instead of the cisco (Linksys WRT54G) and it can easily dial the ISP using L2TP. But this is not a good solution as I need the cisco for site-to-site VPN. I really hope there is a good solution for this problem...
Reboot and Factory Default Reset on ISA500 Series Integrated Security Appliances
Reboot or restart of the network device is made when certain changes in the settings need reboot or if the device is frozen. The configuration...
WAN Quality of Service (QoS) Policy Profiles Settings on ISA500 Series Integrated Security Appliances
Wide Area Network (WAN) Quality of Service (QoS) policy profiles manage traffic through classed-based profiles. These pro...
Cisco QuickVPN Installation Tips for Windows Operating Systems
For a video showing installation tips on Quick VPN, visit http://youtu.be/hHu2z6A78N8
Cisco QuickVPN is a free software designed for remote access to a ne...