Unable to configure Zoiper - "we are unable to connect to your PBX with the information you have provided"

Question

Hello All,

                   I have installed  Freeswitch in Ubuntu with the help of this url, and tried creating an account  based on the configuration given. But when trying to create a account  I am  getting  the error "we are unable to connect to your PBX with the information you have provided".

Can anyone help me in resolving the above error.

Thanks in advance

Sundaram.G