General protection fault!

History: SetNetMode <- UActorChannel::ReceivedBunch <- (Actor BlueSuperShockBeam) <- UChannel::ReceivedSequencedBunch <- Direct <- UChannel::ReceivedRawBunch <- DispatchDataToChannel <- BunchData <- UNetConnection::ReceivedPacket <- UNetConnection::ReceivedRawPacket <- UTcpNetDriver::TickDispatch <- UpdatePreNet <- ULevel::Tick <- (NetMode=3) <- TickLevel <- UGameEngine::Tick <- Level Face Classic <- UpdateWorld <- MainLoop

How can I fix this? It always bothers me twice a game and causes my ut to crush!