1. Reinstall a clean copy of L2
http://www.fileplanet.com/176081/170000/fileinfo/Lineage-2---Interlude-Client
2. Download this patch Tehgamers-updater http://www.dragonshadowclan.com/Downloads/Tehgamers-updater.exe
3. Copy above patch named Tehgamers-updater.exe to here "C:\Program Files\Lineage II" or what ever Directory you have installed L2 to.
4.Run Patch and let it autoupdate your client.
Thats all with this you will have a fully updated Interlude client...