I started getting this error when I open Cisco AnyConnect,
VPN Service not available
the vpn agent service is not responding please restart this application after a minute
Everything was okay. The only thing I suspect is altering the hosts file. I restored it. I tried lot of things, such as flushing the sockets and appending
\r\n in the hosts file. It worked for a while and then broke again.
I'm using Windows 7 64-bit and Cisco AnyConnect 3.1.5152.