SSTP VPN Server/Client (Error 0x800b0109)

Hi feriends , 
I have a problem with SSTP VPN Server/Client 
I configured a server with windows server 2008R2 as RRAS and CA and I'm trying to set this server as sstp vpn server. 
So I used the microsoft step by step instruction to setup the server.(http://technet.microsoft.com/en-us/library/cc731352(v=ws.10).aspx) 
But the server is not a domain member and the client wants to connect it through the internet. 
On client side I installed a certificate from CA/RRAS Server and copied it to tusted root CA node in certificate (Local Machine) and add this record to host file : 
46.208.61.30 SSTPVPNSRV 
Which SSTPVPNSRV is the name of the server. 
But when I try to connect the SSTP VPN connection, I give this error : 
"A certificate chain processed but terminated in a root certificate which is not trusted by the trust provider." 
Is there anyone who has experienced it? 
Is there something wrong with my settings or I forget a step? 
I attached the diagram picture of my scenario to this discussion. 
Any help . . .