Starting with all settings on SP2/ITSP B at Default, these are the only settings required to register and make/receive calls with Sipgate:
Service Providers -> ITSP Profile B -> SIP -> ProxyServer :
sipgate.comVoice Services -> SP2 Service -> X_ServProvProfile : B
Voice Services -> SP2 Service -> AuthUserName : (sip username)
Voice Services -> SP2 Service -> AuthPassword : (sip password)
A STUN server is a good addition. I use:
Service Providers -> ITSP Profile B -> General -> STUNEnable : (checked)
Service Providers -> ITSP Profile B -> General -> STUNServer :
stun.ideasip.comService Providers -> ITSP Profile B -> General -> X_STUNServerPort : (Default)
My Sipgate account works perfectly with these settings.