I have tried every combination to allow unauthenticated access to WCF as in "LocalUser" accounts, in IIS without success. Here is what I've most recently tried:

wsHttpBinding with Message security and mode set to "None". IIS anonymous access enabled, all others disabled, folder level access at default (but granted read access to "Users" which is all users in our domain).

I understand I may not have provided enough information to solve the issue, but perhaps somebody can point me in the right direction - is this likely to be a IIS configuration issue or a WCF configuration issue... if WCF, is it likely to be a client level or server level issue?

The error I get when attempting to access here is "User is not authenticated". We have ASMX services in the domain which are behaving properly, I am the first developer using WCF here.