The passive ability "Expose Weak Point"and "Lightning Barrier" writes an error to gameserver:

[Eduardo]

Log Gameserver: [WARN ] 2022-08-18 22:43:36 TargetType: Outdated Skill Expose Weak Point(5565,1) with target type ENEMY_ONLY used on L2MonsterInstance:Lilim Slayer(21184)[268447179] by admin [268481292]!

-The ability has a chance to activate when damage is taken, but it doesn't activate, instead of activating, this error appears as many times as it wants to activate.

-The error appears with admin characters, non-admin characters, clean server pack 2.6.3.0, and a newly created database independent of the class that shares this ability.

-Note: When it's player vs player it works perfectly, only when it's any NPC vs player.

-Note 2: The skill "Lightning Barrier" 5591.1 does something similar.

[Zoey76]

It’s a warning, not an error, you can ignore it for now if the skill is working.