hvad betyder no label fejl?

får denne fejl meddelelse under spillet army operation :
No Label

OS: Windows XP 5.1 (Build: 2600)
CPU: GenuineIntel Unknown processor @ 2402 MHz with 511MB RAM
Video: NVIDIA GeForce FX 5200 (4403)

Assertion failed: TopChunk==NULL [File:UnMem.cpp] [Line: 42]

History:  <- FMemStack::InitStack <- FMemStack::Exit <- FD3DInternalState::Commit::VertexStreams <- FD3DInternalState::Commit <- FD3DRenderInterface::DrawPrimitive <- FProjectorRenderBatch::Render <- RenderLevel <- FLevelSceneNode::Render <- FPlayerSceneNode::Render <- UGameEngine::Draw <- UWindowsViewport::Repaint <- UWindowsClient::Tick <- ClientTick <- UGameEngine::Tick <- UpdateWorld <- MainLoop