reference link

Guide:
Download L2net and install, start it, donate if you can and then goes on Help -> Hosts
write these lines in the hosts file, and put a # in front of the other lines related to lineage 2 (except for gameguard ones)
Code:
127.0.0.1 L2authd.lineage2.com 127.0.0.1 L2testauthd.lineage2.com #127.0.0.1 lineage2.gigarent.it
In L2NET, Help -> Hosts
Delete the # from the line
Code:
#127.0.0.1 lineage2.gigarent.it
Version: T1,5 Protocol: 831
Select IG mode (oog won't work on my opinion)
Server IP: 85.18.73.4
then click Listen
In Lineage2 Client window, login as usual, select server and character, enter in the game.
In L2NET, Help -> Hosts
Insert again the # in the line
Code:
127.0.0.1 lineage2.gigarent.it






