I've previously talked about using WSDL extensions to provide custom modifications to the WSDL import and export process. Making modifications to an existing WSDL document or to the existing WSDL processing is a great way to make small changes when the default behavior almost gets you to where you want. However, you may have noticed that these mechanisms are a little cumbersome for providing a complete overhaul of metadata; that's because a WSDL extension is primarily a hook to supply user extensibility before or after certain steps in the WSDL import or export process. When making large-scale modifications, another tool in your toolbox is to entirely jump out of the built-in WSDL processing. The ExternalMetadataLocation property on the ServiceMetadataBehavior is one of the ways that you can opt out of the standard process. By supplying an external metadata location, you provide to clients a reference to an independent location for retrieving metadata. You might base the contents of that external metadata on the metadata files normally generated by the service (the disco.exe tool in the Windows SDK is a good way to generate all of those metadata files at once) or you might go completely wild and make the external metadata have no relationship at all to the normally generated metadata files. Next time: Avoid Exceptions in Faults Read More...