installation failed 5.5.5

i have down loaded scilab 5.5.5 from scilab.org. while the time of installing i got a message "The application has failed to start because normaliz.dll was not found. reinstalling may fix the problem." i tried may time but failed. but i tried it from scilab.in and succeeded. i am using wndows xp. what i have to do to get 5.5.5 from scilab.org