Lineage II requires that TCP ports 2106, 7777, 2009, and 80 are fully unrestricted and accessible inbound and out. If you are connecting to Lineage II while on a campus or business network, please consult your network's administrator to verify that these ports are available. If you are on a Local Area Network (LAN) or behind a router, please make sure that your network's hardware is properly configured.
If you’re having an issue launching the game this can sometimes be caused by 3rd party programs interfering with the game client. We recommend you try disabling all 3rd party programs to see if it has any effect on your issue. For instructions on how to do this please reference the KB article here
Disable AV/FW Software
We’ve seen an array of security software interfere with the game successfully launching. If you were unsuccessful with the MSCONFIG procedure, we suggest temporarily disabling or even removing security software to see if it has any affect on the issue. We do not recommend running your machine without a security application. Please only disable or remove security software as a temporary troubleshooting step.
Open a Technical Support Request
If your issue still persists after trying all the suggested steps please submit a Technical Support Request. We recommend you run a DXDIAG first and attach the results to your support help request. For help with how to do this, please reference the KB Article here.