What is the head end device?
Do you have any debugs turned on over at the head end device.
Can you enable debugs on the head end side to check if the client is event making the attempt to connect?
Is the client going through a firewall or NAT device.
Enable the client logs and set the logging settings to 1-13. Then try to connect and send me the logs.
Let me take a look at those.
Cheers
gilbert