You can get the "Lineage 2 The Chaotic Throne - High Five" client at the following link:
If you have the game already installed on your computer, go directly to step 2.
Download the launcher and place it in your Lineage 2 folder (not inside your system folder!). Example: Partition D:\Programs\Lineage2\Launcher.
Start the game only with the LinIICentury Launcher. Enter your account name and password. Accounts will be created automatically.