Another for the Note To Self listA lot of our sites use a url mapper, so when setting up the sites within IIS we map extension .* to the appropriate aspnet_isapi.dll. I'd got carried away when setting up the webservice and did the same thing, resulting in a The HTTP verb POST used to access path '/WebService/WebService.asmx/DoSomething' is not allowed. error. Removing the .* mapping fixes this.