Follow thisn procedure to fix this problem:
Open inetmgr > Right Click on the RespectiveWebsite Hosting > Select 'Properties' > You Will Be Presented With a Main Options Panel, Where it Says the IP Address That The Sites uis Hosted on, Select 'Advanced' > You Will Be Presented With All IP Addresses The Web site hosting is Hoted On > Click 'Add' Down the Bottom of That Pane > Fill This Pane Out With the Following Options:
IP Addresss: The Default Shared IP (You Should Know This)
Port: 80
Hostname (Something Like That):
website hosting.tld for without
www., just add www. respectively if you want it to be www.
> Click OK & Apply Respectively
I hope that helps, some of the options may not be named correctly, but it should give you a good idea of how to do it.