PPTP IOS VPN Connection Refused?

Hello Guys! I have a question regarding my PPTP Server. I´m enable to connect just fine on windows and my friends have tried to connect aswell from pc and it works.

When i try to connect to my pptp vpn server using my iphone with the correct ip,username and password. its connecting ,authentication and then disconnecting. And gives the following error message “A Connection could not be estalished to the PPP Server. Try reconnecting. If the problem continues, verify your settings and contact your administrator.” I wonder why it gives this error message when i try to connect from my iphone?

I have enabled the following iptables in firewall: " iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE iptables -I FORWARD -p tcp --syn -i ppp+ -j TCPMSS --set-mss 1356 iptables -A INPUT -i eth0 -p tcp --dport 1723 -j ACCEPT iptables -A INPUT -i eth0 -p gre -j ACCEPT iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT iptables -A FORWARD -i ppp+ -o eth0 -j ACCEPT iptables -A FORWARD -i eth0 -o ppp+ -j ACCEPT iptables -A INPUT -p tcp --tcp-flags ALL NONE -j DROP iptables -A INPUT -p tcp ! --syn -m state --state NEW -j DROP iptables -A INPUT -p tcp --tcp-flags ALL ALL -j DROP iptables -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT " Have i missed any rule to enable in order to allow mobile devices to connect to the vpn server?

Sincerly Zyry