Help Me With This

i Have Created A Server But When i Want To Make My Friend GM What Ip I Put The Real Or Hamachi? I Tried Everthing But At His Pc The Game Stop At Requesting User Confirmation And He Dont Login What I Have To Do?
Answer Me Fast Please !

try to use old user

Put his public ip or his hamachi ip
for public ip let him use (whatismyipaddress.com) for hamachi ask him for his hamachi ip ;)