How to create a VB.NET softphone?

Jun 23 2011 9:09 AM

I'm new at this site, I hope you could help me.
I've downloaded a sample program (a VoIP SDK) for the claimed reason, but I'm too noob to use it. Although it has a manual, something isn't working. Can you tell me why?
How should I use it?
Thanks in advance,

(You can find the sample here: http://www.voip-sip-sdk.com/p_179-windows-forms-softphone-vb-net-voip.html)