Swords problem

[Yen]

Server has a custom attack system.
However, when a baddy swings it's sword, I'm being thrown back. It only happens when I use my old computer.
No other players are, only me. My AP is 100. The baddy's attack gani isn't 'sword,' nor is it based off the 'sword' gani.
hurt(), hitplayer(), and so on doesn't show up even once on the server.

What the **** is wrong? I'm running out of patience with these god damn useless bugs popping up out of nowhere.