Hosting a web site in XG firewall

I have a server in a dmz zone that has be published for 9 years behind TMG2010. when i move it behind XG firewall  i get error 403 forbidden when i access the site. I see traffic counting in FW rule so its seems to be working. looked thru many docs and troubleshooting guide to no avail. Put the server back at TMG works as normal. is there some other setting i am missing?