Does the question pertain to a level I've already played?
Check the Walkthroughs first,
I may have already answered your question.
Please do not ask me tech support questions, such as Why
does Deus Ex: Invisible War crash when I do.... ?. Eidos
has a staff dedicated to this already who know more about the
tech issues regarding Deus Ex: Invisible War than I do. Also check
out Eidos
Tech Support Forums