can't access websites internally

hi, we can’t access our websites using the domain names via the intranet, we used to be able to, but then we installed a new firewall and now we can’t, we have all of the ports forwarded correctly in the new firewall. when ever we try to view the wepage using the domain name internally all we get is the default “It Works” page. anyone know how we can resolve this issue. all of the configs look fine.
Many thanks

we got it, it was our DNS that was blocking it