delete all the files related to iTrader... are you using it for a long time, or you just played with it recently??
btw, we can not offer support over someone else's product *(mine actually)... you'll have to post on the official forum, which is here: http://vbenhancer.com/itrader/
This is a new install off a zip file used to setup another website 4 weeks ago. That install went smoothly, but this one never worked.