Irfan,

When you initially open the program you will see the screen below:

You can set default value of Web service Url by editng LiveSupport.exe.config file.

<add key="CuteChatServiceUrlBase" value="http://yoursite.com"/>

If the Web service Url you entered doesn't match the exact location of  CuteSoft_client folder, you will get this error.

 

For example, if your site name is abc.com and you upload CuteSoft_client folder to the root of your web site, the value of Web service Url should be: http://abc.com.