Make sure that you have the right cable pinout and that your ISP has turned on the DSL service. Troubleshoot the DSL connection by watching the modem state of the ADSL interface as the line retrains.
To use the VPN Client, you need
- Direct network connection (cable or DSL modem and network adapter/interface card), or
- Internal or external modem
For further more troubleshoot click this link,
http://www.cisco.com/en/US/docs/security/vpn_client/cisco_vpn_client/vpn_client500_501/release/notes/51client.html#wp1550392