I have the following setup WLC 4402 version 126.96.36.199, 1010 Access points, Each access point's switch port is configured as a trunk along with the WLC's port. My WLAN for internal users works like a charm. MY WLAN for guest is not able to browse the web. I'm using Web Auth Internal with guest username and password.
Any help greatly appreciated.
It very likely be the ACL if it is configured wrongly. Try deleting it. Here is a link to the deployment guide for guest access using Lan controllers.