IIS supports specifying multiple IIS bindings per site, which results in multiple base addresses per scheme. A WCF service hosted under a site allows binding to only one baseAddress per scheme.
So if you get an error like this “This collection already contains an address with scheme http wcf”, you may want to look at the following:
Solution in .Net Fx 3.0:Supporting Multiple IIS Bindings Per Site
Solution in .Net Fx3.5: BaseAddressPrefixFilters